Endocrine system role – Chemicals – Environment

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Why is it important
for life?

The endocrine system controls growth and development during
childhood, regulation of bodily functions in adulthood, and
the reproductive process.

The endocrine system is important for the control and regulation
of all the major functions and processes of the body:

• Energy control
• Reproduction
• Immunity
• Behaviour (e.g. fight or flight response)
• Growth and development

Hormones interact to maintain the above functions and help
to regulate our responses to disease, our ability to reproduce
and even influence our relationships and behaviour (such as
mother:child bonding).

As can be seen, many of the hormones act on tissues and organs
at several sites throughout the body. The target cells in these
tissues or organs contain specialised structures (receptors)
to which only a specific hormone can bind. The response that
occurs in the cell will depend on the receptor and cell type,
and the effects of other hormones to which that cell may also
be exposed. Also, a hormone that stimulates the activity of
one cell type may suppress that of a different cell type.

A similar, but not identical, endocrine system to that of humans
is found in nearly all vertebrates including other mammals,
fish, amphibians, reptiles and birds, although the precise structures
and roles of the various organs and hormones differ between
different groups, particularly in relation to the different
life cycle and development stages in different species. Invertebrates
such as molluscs, crustacea and insects also have endocrine
systems that control a similar range of body functions although
these have evolved along markedly different lines to those of
vertebrates.

The main glands and hormones of mammals are:

Gland	Hormones	Target organs	Main actions
Hypothalamus (specialised region of the brain)	Releasing or inhibiting hormones (e.g. growth hormone releasing hormone (GHRH), somatostatin, corticotropin releasing hormone (CRH), arginine vasopressin (AVP), gonadotropin releasing hormone (GnRH) & thyrotropin releasing hormone (TRH)	Anterior pituitary	Controls production/release of other hormones
	Antidiuretic hormone (ADH)	Kidney	Controls water loss
	Oxytocin (OT) -released via the posterior pituitary (neurohypothysis)	Uterus, Mammary glands
Anterior pituitary [adenohypophysis]	Luteinizing hormone (LH)	Gonads	Control of ovarian oestrus cycle & Leydig cells in testis Control of ovarian oestrus cycle & Sertoli cells in testis Promotes milk production
	Follicle stimulating hormone (FSH)	Gonads
	Prolactin	Breast
	Thyroid stimulating hormone (TSH)	Thyroid glands	Stimulates T4 production/release Affects growth and metabolism
	Growth hormone (GH)	Generalised
	Adrenocorticotropic hormone (ACTH)	Adrenal glands	Stimulates adrenal cortex
Thyroid	Thyroxine (T4) [active form is tri-iodothyronine T3]	Many tissues	Control of general metabolic rate, also important for development and reproductive functions
Adrenal [suprarenal] cortex	Glucocorticoids (e. g. cortisol & corticosterone	Many tissues	Diverse effects on inflammation and protein synthesis
	Mineralocorticoids (e.g. aldosterone)	Many tissues	Salt balance
Adrenal [suprarenal] medulla	Adrenaline (Epinephrine)	Many tissues	Glycogenolysis, lipid mobilisation, smooth muscle contraction, cardiac function
	Noradrenaline (Norepinephrine)	Many tissues	Lipid mobilisation, arteriole contraction
Pancreas	Insulin	Many tissues including liver, adipose tissue & muscle	Facilitates utilisation of glucose by cells & prevents excessive glycogen breakdown in liver & muscle
	Glucagon	Many tissues including liver, adipose tissue & muscle	Prevents hypoglycaemia through action on carbohydrate, fat & protein metabolism
Gonads	Sex steroids (e.g. oestradiol, testosterone, progesterone)	Brain, gonads, accessory sex organs	Sexual development & maintainance of reproductive function and behaviour

Endocrine System | John T. Milken Department of Medicine Division of Endocrinology, Metabolism and Lipid Research

Endocrinology

Endocrinology is the study of the body’s endocrine glands. Endocrine glands produce hormones, which are molecules that serve as messengers throughout the body. Each hormone is designed to trigger a very specific response in a specific part of the body. Endocrinologists are physicians who specialize in diagnosing and treating disorders of the endocrine system.

The Endocrine Glands

Adrenal Glands

Location: There are two adrenal glands located on the top of each kidney.

Hormones produced: Adrenaline, aldosterone and cortisol.

Purpose: Hormones of the adrenal glands maintain sodium, chloride and potassium levels in the blood, maintain blood pressure, help control kidney function and control overall fluid concentrations in the body.

Hypothalamus

Location: Within the brain. Hormones produced: Many hormones that affect the brain, nervous system, and other glands.

Purpose: Hormones of the hypothalamus regulate an extremely wide range of basic body functions, such as heart rate, blood pressure, sleep, appetite, thirst and regulation of body water and body temperature. These hormones exert their control by acting on the brain, nervous system and other endocrine glands.

Pancreas

Location: Deep in the abdomen behind the stomach.

Hormones produced: Insulin, glucagon, somatostatin and others.

Purpose: Hormones of the pancreas control blood sugar and regulate the use and storage of nutrients such as glucose, amino acids, and triglycerides. The pancreas also plays a role in digestion; it produces digestive enzymes that are secreted into the small intestine.

Parathyroid Glands 

Location: There are four parathyroid glands located in the neck behind the thyroid gland.

Hormone produced: Parathyroid hormone (PTH).

Purpose: PTH maintains the correct levels of calcium and phosphorous throughout the body.

Pituitary Gland 

Location: Base of the brain.

Hormones produced: Thyroid stimulating hormone (TSH), follicle stimulating hormone (FSH), adrenocorticotropic hormone (ACTH), growth hormone, and others.

Purpose: The pituitary plays a key role in regulating growth and development, metabolism and reproduction. It controls the activity of many other endocrine glands, including the thyroid, ovaries, adrenal and others. Examples of pituitary hormones and their functions: growth hormone regulates growth; ACTH stimulates the adrenal glands to produce cortisol; TSH signals the thyroid gland to produce thyroid hormone; luteinizing hormone and follicle-stimulating hormone regulate ovulation and estrogen and progesterone production in women, and sperm formation and testosterone production in men.

Reproductive Glands—Ovaries and Testicles

Location: Ovaries (in women) are located inside the lower abdomen. Testes (in men) are located underneath the penis.

Hormones produced: Ovaries produce estrogen and progesterone. Testes produce a variety of “male” hormones called androgens, including testosterone.

Purpose: Reproductive hormones regulate development and reproductive functions. Estrogen controls development of female sex characteristics during puberty and also stimulates growth of the uterine lining during the menstrual cycle. Progesterone helps fertilized eggs to attach to the uterus and develop into an embryo. Testosterone is responsible for the development of male sex characteristics during puberty and for stimulating sperm maturation. Androgens enhance the growth of body tissues, especially muscle.

37.1A: Hormone Functions – Biology LibreTexts

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1. Key Points
2. Key Terms
3. The Endocrine System: Hormones

The endocrine system plays a role in growth, metabolism, and other processes by releasing hormones into the blood.

Learning Objectives

• Evaluate hormones and their purpose in the body

Key Points

• Hormones serve as chemical messengers in the body and help maintain homeostasis.
• Hormones are released into bodily fluids, like blood, which carry them to target cells.
• Target cells respond to a hormone when they express a specific receptor for that hormone.
• Hormones also play a role in the regulation of cell death, the immune system, reproductive development, mood swings, and hunger cravings.
• In the adrenal gland, epinephrine and norepinephrine regulate responses to stress; in the thyroid gland, thyroid hormones regulates metabolic rates.

Key Terms

• target cell: any cell having a specific receptor for a hormone
• hormone: any substance produced by one tissue and conveyed by the bloodstream to another to affect physiological activity
• endocrine system: a control system of ductless glands that secrete hormones which circulate via the bloodstream to affect cells within specific organs

The Endocrine System: Hormones

An animal’s endocrine system controls body processes through the production, secretion, and regulation of hormones. Hormones serve as chemical “messengers” that function in cellular and organ activity to maintain the body’s homeostasis. Maintaining homeostasis within the body requires the coordination of many different systems and organs. Communication between neighboring cells and between cells and tissues in distant parts of the body occurs through the release of hormones into body fluids (usually blood), which carry them to their target cells. Target cells, those having a receptor for a signal, respond to a hormone when they express a specific receptor for that hormone. Cellular recipients of a particular hormonal signal may be one of several cell types that reside within a number of different tissues, as is the case for insulin, which triggers a diverse range of systemic physiological effects. Different tissue types may also respond differently to the same hormonal signal.

By releasing hormones, the endocrine system plays a role in growth, metabolism, and sexual development. Hormones also play a role in induction or suppression of cell death, activation or inhibition of the immune system, mood swings, and hunger cravings. In humans, common endocrine system diseases include thyroid disease and diabetes mellitus.

Examples of endocrine glands include the adrenal glands, which produce hormones, such as epinephrine and norepinephrine that regulate responses to stress, and the thyroid gland, which produces thyroid hormones that regulate metabolic rates. In organisms that undergo metamorphosis, the process is controlled by the endocrine system. The transformation from tadpole to frog, for example, is complex and nuanced to adapt to specific environments and ecological circumstances.

Figure \(\PageIndex{1}\): Hormones in metamorphosis: The process of amphibian metamorphosis, as seen in the tadpole-to-frog stages shown here, is driven by hormones.

The Endocrine System – Human Nutrition [DEPRECATED]

Chapter 2. The Human Body

Figure 2.19 The Endocrine System

The functions of the endocrine system are intricately connected to the body’s nutrition. This organ system is responsible for regulating appetite, nutrient absorption, nutrient storage, and nutrient usage, in addition to other functions, such as reproduction. The glands in the endocrine system are the pituitary, thyroid, parathyroid, adrenals, thymus, pineal, pancreas, ovaries, and testes. The glands secrete hormones, which are biological molecules that regulate cellular processes in other target tissues, so they require transportation by the circulatory system. Adequate nutrition is critical for the functioning of all the glands in the endocrine system. A protein deficiency impairs gonadal-hormone release, preventing reproduction. Athletic teenage girls with very little body fat often do not menstruate. Children who are malnourished usually do not produce enough growth hormone and fail to reach normal height for their age group. Probably the most popularized connection between nutrition and the functions of the endocrine system is that unhealthy dietary patterns are linked to obesity and the development of Type 2 diabetes. The Centers for Disease Control and Prevention (CDC) estimates that twenty-six million Americans have Type 2 diabetes as of 2011. This is 8.3 percent of the US population. Counties with the highest incidence of obesity also have the highest incidence of Type 2 diabetes. To see how the rise in obesity in this country is paralleled by the rise in Type 2 diabetes, review this report by the CDC.
https://www.cdc.gov/diabetes/statistics/slides/maps_diabetesobesity_trends.pdf 

What is the causal relationship between overnutrition and Type 2 diabetes? The prevailing theory is that the overconsumption of high-fat and high-sugar foods causes changes in muscle, fat, and liver cells that leads to a diminished response from the pancreatic hormone insulin. These cells are called “insulin-resistant.” Insulin is released after a meal and instructs the liver and other tissues to take up glucose and fatty acids that are circulating in the blood. When cells are resistant to insulin they do not take up enough glucose and fatty acids, so glucose and fatty acids remain at high concentrations in the blood. The chronic elevation of glucose and fatty acids in the blood also causes damage to other tissues over time, so that people who have Type 2 diabetes are at increased risk for cardiovascular disease, kidney disease, nerve damage, and eye disease.

Career Connection

Do your part to slow the rising tide of obesity and Type 2 diabetes in this country. On the individual level, improve your own family’s diet; at the local community level, support the development of more nutritious school lunch programs; and at the national level, support your nation’s nutrition goals. Visit the CDC Diabetes Public Health Resource website at https://www.cdc.gov/diabetes/. It provides information on education resources, projects, and programs, and spotlights news on diabetes. For helpful information on obesity, visit https://www.cdc.gov/obesity/. The CDC also has workplace web-based resources with the mission of designing work sites that prevent obesity. See https://www.cdc.gov/workplacehealthpromotion/index.html or more details.

Hypothalamus: Function, hormones, and disorders

The hypothalamus is a small but important area in the center of the brain. It plays an important role in hormone production and helps to stimulate many important processes in the body and is located in the brain, between the pituitary gland and thalamus.

When the hypothalamus is not working properly, it can cause problems in the body that lead to a wide range of rare disorders. Maintaining hypothalamic health is vital because of this.

The hypothalamus’ main role is to keep the body in homeostasis as much as possible.

Homeostasis means a healthful, balanced bodily state. The body is always trying to achieve this balance. Feelings of hunger, for example, are the brain’s way of letting its owner know that they need more nutrients to achieve homeostasis.

The hypothalamus acts as the connector between the endocrine and nervous systems to achieve this. It plays a part in many essential functions of the body such as:

• body temperature
• thirst
• appetite and weight control
• emotions
• sleep cycles
• sex drive
• childbirth
• blood pressure and heart rate
• production of digestive juices
• balancing bodily fluids

As different systems and parts of the body send signals to the brain, they alert the hypothalamus to any unbalanced factors that need addressing. The hypothalamus then responds by releasing the right hormones into the bloodstream to balance the body.

One example of this is the remarkable ability of a human being to maintain an internal temperature of 98. 6 °Fahrenheit (ºF).

If the hypothalamus receives a signal that the internal temperature is too high, it will tell the body to sweat. If it receives the signal that the temperature is too cold, the body will create its own heat by shivering.

To maintain homeostasis, the hypothalamus is responsible for creating or controlling many hormones in the body. The hypothalamus works with the pituitary gland, which makes and sends other important hormones around the body.

Together, the hypothalamus and pituitary gland control many of the glands that produce hormones of the body, called the endocrine system. This includes the adrenal cortex, gonads, and thyroid.

Hormones secreted by the hypothalamus include:

• antidiuretic hormone, which increases how much water is absorbed into the blood by the kidneys
• corticotropin-releasing hormone, which helps regulate metabolism and immune response by working with the pituitary gland and adrenal gland to release certain steroids
• gonadotropin-releasing hormone, which instructs the pituitary gland to release more hormones that keep the sexual organs working
• oxytocin, a hormone involved in several processes, including the release of a mother’s breast milk, moderating body temperature, and regulating sleep cycles
• prolactin-controlling hormones, which tell the pituitary gland to either start or stop breast milk production in lactating mothers
• thyrotropin-releasing hormone activates the thyroid, which releases the hormones that regulate metabolism, energy levels, and developmental growth

The hypothalamus also directly influences growth hormones. It commands the pituitary gland to either increase or decrease their presence in the body, which is essential for both growing children and fully developed adults.

Share on PinterestThe pituitary gland and hypothalamus are connected by function. It can be difficult to distinguish a disorder as hypothalamic or pituitary.

A hypothalamic disease is any disorder that prevents the hypothalamus from functioning correctly. These diseases are very hard to pinpoint and diagnose because the hypothalamus has a wide range of roles in the endocrine system.

The hypothalamus also serves the vital purpose of signaling that the pituitary gland should release hormones to the rest of the endocrine system. As it is difficult for doctors to diagnose a specific, incorrectly functioning gland, these disorders are often called hypothalamic-pituitary disorders.

In these cases, there are some hormone tests that doctors might prescribe to get to the root of the disorder.

Causes and risk factors

The most common causes of hypothalamic diseases are injuries to the head that impact the hypothalamus. Surgeries, radiation, and tumors can also cause disease in the hypothalamus.

Some hypothalamic diseases have a genetic link to hypothalamic disease. For instance, Kallman syndrome causes hypothalamic problems in children, most noticeably delayed or absent puberty, accompanied by an impaired sense of smell.

Hypothalamus problems also appear to have a genetic link in Prader-Willi Syndrome. This is a condition in which a missing chromosome leads to short stature and hypothalamic dysfunction.

Additional causes of hypothalamic disease can include:

• eating disorders, such as bulimia or anorexia
• genetic disorders that cause excess iron buildup in the body
• malnutrition
• infections
• excessive bleeding

Symptoms of hypothalamus disorders

Symptoms of hypothalamus disorders vary depending on what hormones are in short supply.

Children might show signs of abnormal growth and abnormal puberty. Adults might show symptoms linked to the various hormones their bodies cannot produce.

There is usually a traceable link between the absent hormones and the symptoms they produce in the body. Tumor symptoms might include blurred vision, loss of vision, and headaches.

Low adrenal function might produce symptoms such as weakness and dizziness.

Symptoms caused by an overactive thyroid gland include:

• sensitivity to heat
• anxiety
• feeling irritable
• mood swings
• tiredness and difficulty sleeping
• lack of sex drive
• diarrhea
• constant thirst
• itchiness

As the hypothalamus plays such a vital role in the body, it is very important to keep it healthy. While a person cannot fully avoid genetic factors, they can take dietary steps towards ideal hypothalamus health on a daily basis to reduce the risk of hypothalamic disease.

The hypothalamus controls the appetite, and the foods in the diet influence the hypothalamus. Studies have shown that diets high in saturated fats can alter the way the hypothalamus regulates hunger and energy expenditure.

Sources of saturated fats include lard, meat, and dairy products. Research has also demonstrated that diets high in saturated fats might have an inflammatory effect on the body.

This can make the immune system overactive, increasing the chances of it targeting healthy body cells, increasing inflammation in the gut, and altering the natural working of the body.

Diets high in polyunsaturated fats, like omega-3 fatty acids, can help to reverse this inflammation. These fats might be a safe alternative to other types of oils and fats. Foods with high omega-3 content include fish, walnuts, flax seeds, and leafy vegetables.

Additional healthy dietary choices to support the hypothalamus and best brain function include:

• vitamin-rich fruits and vegetables
• vitamin C
• B-vitamins

A working hypothalamus is one of the most important parts of the body, and it usually goes unnoticed until it stops working properly. Following these dietary tips can help to keep the hypothalamus happy and working well.

Q:

Why is the hypothalamus so important?

A:

The hypothalamus is the endocrine system’s main switchboard. Most of the body’s critical hormones, which promote growth, metabolism, and normal functioning, are prompted by chemical signals from the hypothalamus.

These hormones, in turn, communicate with the hypothalamus to provide feedback about the body’s functional status. Damage to the hypothalamus can impair one or all of these hormone systems and lead to disastrous consequences, causing the complete shutdown of hormone production.

Daniel Murrell, MDAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

Endocrine System | BioNinja

The endocrine system is a system of ductless glands that release chemicals (hormones) into the blood to regulate body functions

• A hormone is a chemical messenger that is transported via the bloodstream to act on distant target cells
• Hormones are specific and will only activate cells or tissues that possess the appropriate target receptor
• The endocrine system is slower to initiate, but has a more prolonged response when compared to the nervous system

Endocrine Signalling

Endocrine Glands

Endocrine glands secrete their product (hormones) directly into the bloodstream, rather than through a duct (e.g. exocrine gland)

• Major endocrine glands include the pancreas, adrenal gland, thyroid gland, pineal gland and the gonads (ovaries and testes)
• The hypothalamus and pituitary gland are neuroendocrine glands and function to link the nervous and endocrine systems
• Some organs may also secrete hormones despite not being endocrine glands (e.g. adipose tissue secretes leptin)

Examples of Endocrine Glands

Hypothalamus

The hypothalamus is the section of the brain that links the nervous and endocrine systems in order to maintain homeostasis

• It receives information from nerves throughout the body and other parts of the brain and initiates endocrine responses
• It secretes certain neurochemicals (called releasing factors) into a portal system which stimulate or inhibit the pituitary gland
• It also secretes certain hormones directly into the bloodstream via neurosecretory cells that extend into the pituitary gland

The pituitary gland lies adjacent to the hypothalamus and is in direct contact due to a portal blood system

• The pituitary gland is often referred to as the ‘master gland’, as it controls the secretion of a number of other endocrine glands
• The pituitary gland receives instructions from the hypothalamus and consists of two lobes (anterior and posterior lobe)
  • The anterior lobe (adenohypophysis) releases hormones in response to stimulation by hypothalamic releasing factors
  • The posterior lobe (neurohypophysis) releases hormones produced by the hypothalamus itself (via neurosecretory cells)

The Role of the Hypothalamus and Pituitary Gland in Endocrine Function

The Nervous and Endocrine Systems

While neurons are the building blocks of the body’s communication system, it is the network of neurons that allow signals to move between the brain and body. These organized networks, composed of up to 1 trillion neurons, make up what is known as the nervous system.

The human nervous system has two parts: the central nervous system, which includes the brain and spinal cord, and the peripheral nervous system, which is composed of nerves and nerve networks throughout the body.

The endocrine system is also essential to communication. The system utilizes glands located throughout the body that secrete hormones. The hormones regulate a variety of bodily functions, including metabolism, digestion, blood pressure, and growth. The endocrine system is not directly linked to the nervous system, but the two interact in a number of ways.

The Central Nervous System

The central nervous system (CNS) is made up of the brain and spinal cord. The primary form of communication in the CNS is the neuron. Together, the brain and the spinal cord are the literal “center” of the body’s communication system.

The brain and spinal cord are vital to human life and functioning.

The body employs a number of protective barriers to surround them, including the bone (skull and spine) and membraneous tissue known as meninges. The brain and spine are suspended in a protective liquid known as cerebrospinal fluid.

The CNS is responsible for processing every sensation and thought that you experience. The sensory information that is gathered by receptors throughout the body. It then passes the information on to the central nervous system. The CNS also sends messages to the rest of the body to control movement, actions, and responses to the environment.

The Peripheral Nervous System

The peripheral system (PNS) is composed of nerves that extend outside of the central nervous system. The nerves and nerve networks that make up the PNS are actually bundles of axons from neuron cells. The nerve bundles can be relatively small or large enough to be easily seen by the human eye.

The PNS is further divided into two different systems: the somatic nervous system and the autonomic nervous system.

Somatic Nervous System

The somatic nervous system transmits sensory communications. It is responsible for voluntary movement and action. It is composed of sensory (afferent) neurons and motor (efferent) neurons.

Sensory neurons carry information from the nerves to the brain and spinal cord while motor neurons transmit information from the central nervous system to the muscle fibers.

Autonomic Nervous System

The autonomic nervous system is responsible for controlling involuntary functions such as heartbeat, respiration, digestion, and blood pressure. The system is also involved in human emotional responses such as sweating and crying.

The autonomic nervous system is subdivided into the sympathetic nervous system and parasympathetic nervous system.

• Sympathetic nervous system: The sympathetic nervous system controls the body’s response to an emergency. When the system is aroused, your heart and breathing rates increase, digestion slows or stops, the pupils dilate and you begin to sweat. Also known as the fight-or-flight response, the system is preparing your body to either fight the danger or flee.
• Parasympathetic nervous system: The parasympathetic nervous system counters the sympathetic system. After a crisis or danger has passed, the system helps to calm the body by slowing heart and breathing rates, resuming digestion, contracting the pupils, and stopping sweating.

The Endocrine System

The endocrine system is composed of glands that secrete chemical messengers known as hormones. Hormones are carried in the bloodstream to specific areas of the body, including the organs and body tissues.

The pineal gland, the hypothalamus, the pituitary gland, the thyroid, the ovaries, and the testes are some of the most important glands in the body. Each of these glands works in a number of unique ways in specific areas.

The endocrine system is not a part of the nervous system, but it is still essential to communication throughout the body.

The hypothalamus connects these two important communication systems. The hypothalamus is a tiny collection of nuclei that is responsible for controlling an astonishing amount of human behavior.

Located at the base of the forebrain, the hypothalamus regulates basic needs such as sleep, hunger, thirst, and sex drive. It’s also involved in producing our emotional and stress responses. The hypothalamus controls the pituitary glands, which, in turn, controls the release of hormones from other glands that are part of the endocrine system.

90,000 Iodine deficiency: symptoms and prevention

October 21 – World Iodine Deficiency Day.

The main freelance endocrinologist of the Department of Health of Sevastopol, an endocrinologist of the Department of Endocrinology of the City Hospital No. 1 named after V.I. N.I. Pirogova Olga Vladimirovna Vlasova .

Why do we need iodine?

– Iodine is an essential trace element for the functioning of the body.

Iodine is the main component of thyroid hormones, which regulates our metabolism.

The human body normally contains 15-20 mg of iodine, 70-80% of them accumulate in the thyroid gland.

How common is iodine deficiency in our country?

– Iodine deficiency is determined throughout the territory of the Russian Federation, the city of Sevastopol belongs to the region with a zone of mild iodine deficiency.

The bulk of Russians experience iodine deficiency to varying degrees, many suffer from various iodine deficiency diseases.

What causes iodine deficiency?

– For children – retarded growth and physical development, mental retardation, decreased efficiency for learning.

For adults – a decrease in attention and the ability to perceive information, memory problems, during pregnancy, it is dangerous to the risk of miscarriage, stillbirth, congenital anomalies in the child.

What diseases can occur with iodine deficiency?

– Iodine deficiency leads to various diseases of the thyroid gland.

According to the WHO, thyroid diseases are the second most common endocrine disorders (after diabetes mellitus) in terms of their prevalence.

The most common: diffuse non-toxic goiter; nodular and multinodular euthyroid goiter; thyrotoxicosis; hypothyroidism; congenital hypothyroidism.

What is the role of the thyroid gland in the human body?

– The thyroid gland is a small organ weighing 15 g, located on the front of the neck, in the shape of a butterfly.

Together with other glands, it is included in the endocrine system of organs that produce biologically active substances – HORMONES.

Its main function is to maintain normal metabolism (metabolism) at the cellular level.

Thyroid hormones stimulate the metabolism in all cells and regulate almost every process in the body – breathing, eating, sleeping, movement, as well as processes in internal organs – from the heartbeat to the functioning of the reproductive system, plays an important role in the functioning of the immune system.

What is the need for iodine and where can I get it?

The need for iodine at different ages is different:

• in children under 5 years old – 90 – 110 μg,

• from 5 to 12 years old – 110-120 mcg,

• in adolescents and adults – 150 μg,

• in pregnant and lactating women – 250 μg,

• in the elderly – 100 mcg per day.

The normal intake of iodine in the human body can be ensured by the method of mass, group and individual iodine prophylaxis.

Mass iodine prophylaxis is the most effective and economical method of replenishing iodine deficiency and is achieved by eating iodized table salt.

Thanks to universal programs for the iodization of table salt, iodine deficiency has been eliminated in many countries.

In our country, in all regions of the Russian Federation, iodine is not enough, therefore, regular constant iodine prophylaxis is necessary.

Iodized salt is a reliable and safest method of prevention – it is the same salt, but fortified with iodine.

When buying salt, you should pay attention to the expiration date, it should be packed in an opaque plastic bag or foil (there is no iodine in expired salt).

It should be stored in a closed container with a lid, it is better to add salt to the finished food; during heat treatment, the preventive effect of iodized salt is not ensured.

With daily use of iodized salt, the body’s need for iodine is fully replenished and does not require additional intake of iodine-containing preparations. This is the easiest and cheapest way to improve the health of yourself and your children.

Individual and group iodine prophylaxis involves taking medications and food supplements of potassium iodide in physiological doses, especially during those periods when the need for iodine increases.

Risk groups for the occurrence of thyroid pathology: children and adolescents, in view of a lack of iodine in food; pregnant and breastfeeding women.

It should also be noted that thyroid diseases are much more common in women than in men. The selection of groups and control over prevention is carried out by medical specialists.

Which foods contain iodine?

– Foods containing high concentrations of iodine are very useful:

• seaweed,

• sea ​​fish,

• seafood,

• fish fat.

Meat, milk, eggs contain little iodine. It is practically absent in vegetables, fruits, herbs.

The family should have iodized salt in their daily diet. This is the guarantee of the health of the present and future generations, and this already depends on us!

Interviewed by Irina Pichugina

Infographics:

90,000 Thymus – what is it? The role of the thymus in the first year of a child’s life

Thymus (thymus gland) is an important organ of the immune system of children.It is located in the upper chest and consists of two lobes that join at the front of the trachea. The gland grows until puberty, reaching a weight of 30–40 grams, then gradually decreases (reverse development).

It plays a dominant role in the immune, endocrine system. The thymus produces thymosin, thymopoietin, which stimulate the production of antibodies, and also produces T-lymphocytes – white blood cells that destroy abnormal cells with foreign antigens.Another function of the thymus is to prevent abnormal cell growth and to prevent cancer. It should be noted that the thymus plays a leading role in the immunity of a child under three years of age.

The role of the thymus in a child’s life

Before birth and in childhood, the thymus is responsible for the production plus maturation of T-lymphocytes, which protect the body from certain threats, including viruses and bacteria. The thymus is the largest lymphoid organ in newborns, as it produces lymphocytes more actively than other tissues.The gland acts as the “first violin” in the development and improvement of the child’s immune system.

Thymus produces and secretes thymosin, a hormone necessary for the production of T cells. After “maturing” in the gland, they enter the bloodstream and migrate to the lymph nodes and spleen, where they help the immune system fight disease.

In some cases, the function of the thymus gland is reduced, which weakens the immune system, increasing the tendency to infections and allergies. The child suffers from lingering ARVI, the pathology easily becomes chronic.Lack of T-lymphocytes in the body can lead to immunodeficiency diseases characterized by severe sweating, swelling and / or sore throat, swelling of the lymph nodes, depression.

Malnutrition and protein deficiency at an early age causes slow or limited growth of the thymus, thereby “undermining” the normal functioning of lymphocytes. This is why a balanced diet with sufficient protein is important.

Doctors in this field

Thymus pathology

Main types of thymus pathology:

• Aplasia – absence or underdevelopment of the thymus
• Hypo- and dysplasia – underdevelopment of the thymus
• Accidental involution – reduction of the thymus gland, under the influence of hormonal imbalance, stress, infection
• Atrophy – reduction, replacement of glandular connective tissue, cessation of functioning
• Thymomegaly – an increase in the mass and volume of the thymus parenchyma above the age norm while maintaining its normal structure
• Hyperplasia – an increase in the glandular tissue, with a violation of the production of immune cells and the functioning of the thymus.
• Thymoma is a tumor of the thymus gland.
• Thymus cyst is a fluid formation of the thymus gland.
• Pathology of the thymus (thymus gland) can cause: the development of a number of immunodeficiency syndromes, autoimmune diseases and some endocrine disorders.

Thymus enlargement in children

A deviation in the size of the thymus in a larger direction and a decrease in its function is denoted by the term “enlarged thymus syndrome” (ADS) in children.The problem of an enlarged thymus is often considered in the light of differential diagnosis with pleurisy, pericarditis, mediastinal tumors, and other pathologies.

It is mistakenly believed that an enlarged thymus in infants or young children is a physiological condition. The peculiarities of the course of infectious diseases in young patients with SSS make it necessary to classify the syndrome as a pathology. Children with LAD are more likely to develop an imbalance of the neuroendocrine plus immune systems.Therefore, patients with revealed thymus enlargement require a full examination and dispensary observation by an endocrinologist, immunologist.

Symptoms of a disease or developmental disorder of the thymus gland

In order to timely identify the pathology of the thymus, parents should pay attention to deviations with varying degrees of severity, which may indicate a disease or developmental disorder of the thymus gland:

• Frequent incidence of colds in a child.
• Protracted course of various diseases, with frequent complications.
• Enlargement of lymphoid tissue – lymph nodes, tonsils, adenoids, tissue on the back of the pharynx.
• Pallor and / or a marbled pattern on the skin of a child.
• Large baby weight at birth.
• The child is rapidly losing and gaining weight quickly.
• Cough outside of a cold, worse when the child is horizontal.
• Sweating, low-grade fever for a long time outside of colds.
• Hyperhidrosis, cold extremities.
• Visible mesh on the baby’s chest.
• Cyanosis (blueing) of the nasolabial triangle during exercise (crying, running)
• Frequent regurgitation, hiccups, belching
• Shortness of breath
• Heart rhythm disturbance

If there is a suspicion of a pathology of the thymus, the doctor may prescribe additional examination methods:

• Ultrasound of the thymus gland,
• CT,
• MRI,
• roentgen,
• complete blood count,
• immunogram,
• biochemical blood test,
• blood for hormones.

Thymic insufficiency is amenable to immunocorrection, which is individually selected by an allergist-immunologist. It is worth noting that timely diagnosis of the pathology of the thymus gland is especially relevant in the first year of a child’s life, when the child begins to be vaccinated.

For detailed advice on the role of the thymus in the life of a child in the first year of life, contact the pediatricians of the medical centers “President-Med”

See also:

Artist: Mamunts Tsovinar Alekseevna

Chief Physician President-Med g.Vidnoe

Higher Medical, Perm State Medical Institute, Faculty of General Medicine, specialty-general medicine

Make an appointment with a doctor

90,000 Hormones and reproductive function in women

Hormones are a specific class of organic substances that are produced by the endocrine system of our body.The function of hormones in the body is primarily regulatory. From the endocrine glands, these substances enter the bloodstream, and then bind to receptors located on the surface of target cells, thereby affecting the metabolic and functional activity of these cells.

Hormones also play an important role in the regulation of reproductive function. From this point of view, the health of a woman is much stronger than that of a man’s depends on the content of certain hormones in the blood. They are responsible not only for puberty, but also for the correct passage of all menstrual cycles and the onset of menopause.Finally, the main female function from the point of view of biology and evolution is childbearing, which also directly depends on the concentration of certain hormones. And without the right balance of these substances, the onset of pregnancy is almost impossible.

The main sex hormones in women

All their diversity can be divided into two large groups:

• estrogens;
• progestogens.

Estrogens are female hormones that are necessary for the feminization of the body, that is, for the development and functioning of the human body according to the female type.They are produced mainly by ovarian follicles. Therefore, the concentration of these substances in girls increases greatly with the onset of puberty, when the ovaries are activated and the first menstruation appears. From this moment until the onset of menopause, the alternation of the phases of the menstrual cycle in a woman’s body will be regulated by estrogens.

In addition to the effect on sexual and reproductive functions, estrogens have a number of other effects on the body:

• suppress degenerative processes in bone tissue;
• are involved in the synthesis of some proteins;
• contribute to the maintenance of normal blood clotting;
• have an anti-atherosclerotic effect by lowering blood cholesterol levels.

The action of hormones of progestogens, primarily progesterone, is the regulation of both the course of pregnancy and the very possibility of conception. These compounds are responsible for preparing the inner surface of the uterus for implantation of a fertilized egg, as well as for the further development of the endometrium in the event of a successful pregnancy. Another function of this class of substances is the correct formation of the mammary gland in girls.

Decreased levels of the hormone progesterone reduce the likelihood of getting pregnant and successfully carrying a baby.In addition, painful sensations during menstruation, as well as a complex of emotional and physiological fluctuations, called premenstrual syndrome, are explained by its insufficiency.

When to see a doctor

Hormonal regulation is an extremely complex, delicate and multicomponent mechanism. All these biologically active substances connect different systems of the body with each other, affect not only their target cells, but also other organs and tissues, and also enhance or suppress each other’s action. That is why, for example, often when diagnosing reproductive problems in women , is required to donate blood for tests of thyroid hormones .

If a health problem is caused by a hormonal imbalance, then only a certified physician can sort it out, find the “weak link” and correct the violation with a point effect. The fact that self-medication can be not only ineffective, but also simply dangerous has long been known. And in the case of endocrine diseases, this statement is triple true – unprofessional intervention in the hormonal sphere can have disastrous consequences for health.

Medical assistance of qualified specialists “CM-Clinic” is the best option for solving any hormonal problems. It should be remembered that the earlier you contact our clinic, the faster the correct diagnosis will be established. And early diagnosis is the most important factor in the success of treatment and minimizing the risk of complications.

What pathologies can affect the reproductive function in a woman

1. Disorders of the endocrine system.

First of all, this, of course, is the pathology of the reproductive organs, in particular, the ovaries. A very common disease is the formation of numerous cysts in them – small cavities filled with mucous contents. Polycystic ovary syndrome is a complex disorder that, in addition to difficulties with the onset and bearing of pregnancy, manifests itself:

• irregular rare periods or even their cessation;
• pain in the lower abdomen;
• male pattern hair;

90,082 obese;

• acne;
• depression or neurosis.

In addition, the reproductive function is influenced by hormones that are produced in other, non-gonads of internal secretion:

• pituitary gland;
• thyroid gland;
• adrenal glands, etc.

Any pathology of these organs can lead to a violation of the hormonal balance, ranging from minor inflammation to serious tumor neoplasms, in which the production of hormones increases or, conversely, decreases.

2. Diabetes mellitus.

This disease also refers to disorders of the organs of the endocrine system (in particular, the pancreas). But due to the widespread prevalence, severe, chronic nature of the course and influence on all systems of the body, without exception, it should be taken out in a separate section. This pathology negatively affects the possibility of conception, and also seriously complicates the bearing of a child. Therefore, a woman with diabetes mellitus throughout pregnancy should be under the close supervision of both a gynecologist and an endocrinologist.

In addition, lack of estrogen is a provoking factor in the development of type 2 diabetes. This is one of the reasons for the increase in the incidence of it among women who have entered the postmenopausal period, when the concentration of these hormones in the blood decreases sharply. Scientists today consider estrogen replacement therapy as one of the most effective measures for the prevention of diabetes mellitus in older women.

3. Changes in body weight.

The amount of adipose tissue in the body and the balance of sex hormones (primarily estrogen) are inextricably linked. This relationship is very complex and diverse, it is influenced by so many external factors that it is impossible to say unequivocally that, for example, increased estrogen in women leads to obesity or vice versa. In such a situation, the doctors of “CM-Clinic” carefully examine all the features of each specific case, using their knowledge and rich practical experience.

There is no doubt only that with excessive weight loss and overweight, the reproductive function of a woman suffers:

• the regularity of menstruation is disrupted;
• the number of ovulations decreases;
• the endometrium does not develop properly;
• increases the risk of complications and pregnancy failure;
• the likelihood of malignant changes in the genitals or mammary glands increases.

Therefore, the most important factor in the successful conception, bearing and childbirth is the normalization of body weight.For this, the specialists of our clinic without fail recommend specially developed programs, including individually selected diets, physiotherapy and medication.

4. Endocrine changes in menopause.

Menopause is a natural period in a woman’s life associated with the extinction of her sexual functions and fertility. This is a fairly long period of time, the peak of which falls on average at about 50 years of age.Menopause is characterized by a whole complex of anatomical, metabolic, physiological and psychological changes, most of which, unfortunately, negatively affect the woman’s well-being.

At the same time, the leading reason for such changes is a sharp decrease in the level of sex hormones. That is why, since the middle of the last century, hormone replacement therapy has been widely used, which includes maintenance doses of estrogens and progesterones. Its purpose can largely smooth out the negative manifestations of menopause, partially slow down age-related changes and even reduce the risk of malignant neoplasms of the mammary glands and the reproductive system.

Gynecologists and endocrinologists “CM-Clinic” successfully correct hormonal disorders in women of any age. In order to get a consultation with our specialists, call by phone: +7 (4912) 77-67-51 or leave a request on the website.

90,000 Women and men of reproductive age | Reproductive health and reproductive rights

Often the cause of problems associated with reproductive health is a person’s ignorance of the basics of reproductive health and ways to preserve it.

Responsible attitude to sex life, lifestyle – all this largely determines the state of your reproductive health. And as a result, it affects the quality and stability of relationships in your family and your well-being in general.

The human reproductive (intended for reproduction) system is laid, like many other organ systems, even during the period of intrauterine development. And the child’s attitude to reproductive health is formed in childhood and adolescence.Initially, this function lies with his parents, and then the person himself takes the baton to take care of his body. The key to the successful formation and functioning of the reproductive system of the unborn baby is the normal course of pregnancy and childbirth in the mother

It is widely believed that only a healthy woman can give birth to a healthy child. But there is evidence that out of 100 couples who cannot have children, in 40-60% of cases, the reason lies precisely in male infertility, which can be caused by sexually transmitted infections, the impact on male health of unfavorable environmental conditions, and also bad habits.

That is why such an important aspect of the health of the unborn child is the preservation of the reproductive health of both his parents – both mom and dad. At the same time, it is the woman’s reproductive system that ensures the birth of a new life, the development and gestation of pregnancy, and, finally, childbirth. So, let’s take a look at the female reproductive system.

According to experts, the optimal age for the first birth is considered to be the period from 20 to 25 years, and for the subsequent ones – the age up to 35 years.After pregnancy and childbirth, it takes about 3 years for full recovery – this is the optimal period between pregnancies. According to scientific research, with a break between pregnancies of less than 2 years, the risk of premature birth and low birth weight increases.

Female reproductive system

The main function of the female reproductive system is reproductive. This means that the conception of a new organism and the bearing of pregnancy occurs in the woman’s body. This function is realized through the interaction of several organs related to the female reproductive system.

And this interaction itself is provided by hormonal regulation, which is the main link in the implementation of the female body of its reproductive function.

The female genital organs are divided into:

• external organs:
  • labia,
  • vagina,
  • crotch.
• internal organs:
  • uterus,
  • cervix,
  • fallopian tubes,
  • ovaries.

Vagina

It is a tube about 8 cm long. The vagina has significant elasticity and the ability to change in size. It contains bundles of muscles that are abundantly supplied with blood.

Cervix

This is a narrow, thick-walled extension of the uterine body leading to the upper part of the vagina. The internal canal of the cervix connects the uterine cavity with the vagina. The cervix opens into the vagina with a uterine opening called the pharynx.The appearance of this area is important for a routine gynecological examination, during which the doctor can identify abnormalities in the mucous membrane of the cervix and vagina. Several cells are scraped from the mucous membrane, which are sent to the laboratory and examined for the presence of cancerous and precancerous diseases. This is called a smear test and should be done by every woman at least every three years.

Uterus

A hollow, pear-shaped organ located in the lower abdomen, behind the bladder.It consists of the most powerful muscles in the human body, which are able to stretch and accommodate a fully formed fetus, push it through the birth canal, and then shrink back to its original size within six weeks. The walls of the uterus are made of dense muscle tissue, and the cavity is covered with a mucous membrane (endometrium), into which a fertilized egg is implanted. If fertilization has not occurred, the mucous membrane is torn away and comes out during menstruation.

Uterine tube

The place where the sperm meet the mature egg shortly after ovulation. The length of the pipe itself is about 10 cm; it has a funnel-shaped end with fringed processes like fingers. The inner lining of the tube is covered with special cells (ciliated epithelium) that guide the mature egg from the ovary into the uterine cavity.

Ovaries

These are endocrine glands located in the abdominal cavity below the navel.Eggs are formed in them, ready for fertilization. The egg is the largest cell in the human body, although it is difficult to see it with the naked eye. Its diameter is 0.2 mm. In addition, the ovaries produce female sex hormones (estrogen and progesterone), which determine the development of female sex characteristics and the nature of menstruation. Nature prudently lays in the ovaries of a newborn girl the rudiments of 400,000 eggs, each of which has a chance of fertilization in the future.And while a woman is in childbearing age, one egg matures every month and enters the fallopian tube. This process is called ovulation.

Functioning of the female reproductive system

The interaction of the organs of the female reproductive system is provided by hormonal regulation. It is hormonal regulation that is the leading link in the implementation of a woman’s reproductive function. There are 5 levels of regulation of the reproductive system:

• The cerebral cortex – produces neurotransmitters – substances that have a direct effect on the functioning of the following levels.
• The hypothalamus is a section in the brain where so-called releasing hormones are synthesized, that is, hormones that regulate the production of pituitary hormones.
• The pituitary gland is a kind of brain process, where hormones are produced that are responsible for the functioning of the endocrine glands and the whole body as a whole. It is there that gonadotropic hormones are produced – luteinizing (LH) and follicle stimulating (FSH), as well as prolactin, which are directly related to the functioning of the ovaries.
• Ovaries – under the influence of gonadotropic hormones, estrogens (female sex hormones), androgens (male sex hormones) and progesterone are produced and released. Androgens are also synthesized in the adrenal cortex.
• Target organs are those organs that are influenced by ovarian and adrenal hormones. First of all, these are the uterus, vagina, vulva, mammary glands, as well as skin, hair, bones, muscles, bladder.

One of the highest departments of hormonal regulation of all internal organs and systems in the human body is the pituitary gland, located in the brain.It is the pituitary gland that regulates the work of the female reproductive system, releasing several “main” hormones, namely:

• follicle-stimulating hormone (FSH), which is responsible for the maturation of follicles in a woman’s ovaries. With insufficient or excessive production of this hormone, a violation of the maturation of follicles occurs, which leads to infertility;
• luteinizing hormone (LH), which is involved in the process of ovulation and the formation of the corpus luteum;
• prolactin (milk hormone), which regulates milk secretion during lactation.Prolactin is a hormone antagonist (rival) of FSH and LH, and with an increase in the production of prolactin in a woman’s body, the work of the ovaries is disrupted, which can also lead to infertility.

In addition to the above hormones, the work of a woman’s reproductive system is regulated by other endocrine glands, the dysfunction of which can also cause infertility and pose a threat to the woman’s reproductive health.

Cyclic changes in a woman’s body

or menstrual-ovarian cycle

In a woman’s body, every month there is a change in the lining of the uterus (menstrual cycle) and a change in the ovaries (ovarian cycle). Thus, it is correct to talk about the menstrual-ovarian cycle.

Menstrual-ovarian cycle

The cycle lasts from the first day of menstruation to the first day of the next menstruation (21 to 35 days). The ovarian (ovarian) cycle takes place in several stages – maturation of the follicle (folliculogenesis), ovulation and the formation of the corpus luteum.

Stage I – folliculogenesis

Under the influence of follicle-stimulating hormone (FSH) at the beginning of the menstrual cycle, the maturation of follicles in the ovary begins – the so-called follicular phase of the menstrual cycle.FSH acts on the primary follicles, which leads to their growth.

Stage 2 – ovulation

In the middle of the menstrual cycle, when the follicle reaches 18-22 mm, the pituitary gland secretes luteinizing hormone (LH), leading to ovulation (rupture of the follicle and the release of an egg from it into the abdominal cavity.

Stage 3 – formation of the corpus luteum

Then, again under the influence of LH, the corpus luteum is formed – the endocrine gland, which secretes progesterone – the “pregnancy hormone”.Under the influence of progesterone, the lining of the uterus changes (luteal phase of the cycle), which prepares it for pregnancy. Lack of function of the corpus luteum can cause infertility.

Menstrual cycle

is a change in the lining of the uterus (endometrium) that occurs in parallel with the ovarian cycle. In the follicular phase of the cycle, the endometrium thickens (under the influence of the hormone estradiol). After ovulation, the corpus luteum hormone (progesterone) causes the endometrial cells to accumulate a large amount of nutrients for the embryo – the luteal phase of the cycle.

In the absence of fertilization, there is a rejection of the mucous membrane of the uterus – menstruation. Together with menstruation, the maturation of the primary follicles occurs – a new menstrual cycle. The time of ovulation (i.e. full maturation of the follicle and the release of a mature egg) is individual for each woman. It can be calculated only approximately, since this process is influenced by various factors. These include diseases of the nervous and endocrine systems, liver, kidneys, etc. Stress and emotional experiences can also cause the accelerated or slowed down development of the egg.

If, as a result of sexual intercourse, a mature egg in the fallopian tube meets the male reproductive cell (sperm), the egg and sperm are combined, and fertilization (conception) occurs. The days after ovulation are the most fertile days. The onset of a girl’s period indicates her puberty and her ability to reproduce a new life.

Changes in other organs and systems

Along with the changes in the genitals as a result of the action of hormones, cyclical changes also occur throughout the woman’s body.

This can be especially noticed in the second phase of the menstrual cycle, when the body is “preparing” for a possible pregnancy. Progesterone causes fluid and salt retention in the body, increased appetite. The consequences of this process are weight gain, engorgement of the mammary glands, and bloating.

In addition, due to a slight edema of the brain tissue, headache, inertia of thinking, drowsiness or insomnia are possible.

Sometimes there are mood swings – tearfulness, irritability, fatigue, lethargy and apathy.With the onset of menstruation, such changes in a woman’s body disappear.

The role of endocrine regulation | Paragraph 58

“Biology. Man. Grade 8”. D.V. Kolesova and others

Question 1. What glands belong to the endocrine system?
The glands of the endocrine system include: pineal gland, pituitary gland, thyroid gland, thymus, adrenal glands, parathyroid glands, thymus gland, pancreas, sex glands.

Question 2. What and where do the glands of internal, external and mixed secretion secrete?
Endocrine glands, or endocrine glands, are those glands that do not have excretory ducts and secrete physiologically active substances (hormones) directly into the internal environment of the body – blood. The glands of external secretion (digestive, lactic, lacrimal, sweat, etc.) secrete substances that are removed through special streams to the surface of the body or into hollow organs. Glands of mixed secretion (pancreas, sex glands) function in two ways.For example, the pancreas contains two types of secretory cells. Some produce digestive juice, which is secreted into the duodenum, and the second, the hormone insulin, which enters the bloodstream.

Question 3. How do nervous and humoral regulation interact?
Together with the nervous endocrine system, the body adapts to environmental conditions. But if the nervous system is structurally rigidly organized, then hormones, moving with the blood, act on all organs and tissues, where they can bind to specific hormone receptors.If the nervous system exerts its influences almost instantly, then the endocrine system develops its effects on the body more slowly, but their duration can also be, in contrast to the nervous ones, very significant. An example of the relationship between the nervous and humoral types of regulation is the hypothalamic-pituitary system. The hypothalamus (part of the diencephalon) catches the level of concentration of hormones in the blood and, depending on the information obtained in this way about the work of the endocrine glands, sends neurohormones and nerve impulses to the pituitary gland (endocrine gland), regulating its work, and the pituitary gland, in turn, – work other endocrine glands.Although, for example, many hormones are synthesized in the hypothalamic region of the diencephalon. So the hypothalamus is a neuroendocrine organ. All activity of the endocrine system is under the control of the nervous system, although the nervous system is constantly controlled by the endocrine system.

Question 4. What is the function of the hypothalamus?
The hypothalamus is a special part of the diencephalon, which is the center of regulation of the endocrine system, the center of regulation of the autonomic nervous system and the center of regulation of needs and emotions.It regulates the functions of the pituitary gland – the main endocrine gland, which controls the activity of all other endocrine glands: the thyroid pancreas, the reproductive adrenal glands, and produces hormones that the posterior lobe of the pituitary gland secretes into the blood. The hormones of the posterior pituitary gland – vasopressin (antidiuretic hormone, ADH) and oxytocin – are peptides. They are produced in the neurons of the hypothalamus, and then they descend along the pozhks into the posterior lobe of the pituitary gland and from there can enter the mole. The main functions of vasopressin are to increase the reabsorption in the renal tubules, which leads to a decrease in urine volume.This hormone takes an important part in the regulation of the constancy of the internal environment of the body, and when it is lacking, a person develops diabetes insipidus – a disease in which the body loses a large amount of pod and some salts. Oxytocin stimulates the smooth muscle contraction of the vas deferens and oviducts, and also plays a critical role in childbirth by stimulating the contraction of the muscles of the uterus. It is also involved in the regulation of water consumption, sexual behavior, emotional responses, sleep, “maternal instinct” and behavioral responses to temperature changes.The hypothalamus is the center that controls much of the motivated behavior.

Question 5. What are the main properties of hormones?
Hormones are specific, that is, they act on strictly defined organs or cells, and are highly active, that is. have an effect in negligible amounts. After their action, the hormones are destroyed, thereby creating an opportunity for the next hormonal action.

Dioxins and their effects on human health

Background

Dioxins are environmental pollutants.They are part of the Dirty Dozen, a group of hazardous chemicals known as persistent organic pollutants. Dioxins are of particular concern due to their high toxic potential. Experiments show that they affect a variety of organs and systems.

Once in the human body, dioxins remain in it for a long time due to their chemical stability and ability to be absorbed by adipose tissues, in which they are then deposited. Their half-life in the body is estimated at 7-11 years.In the environment, dioxins tend to accumulate in the food chain. The concentration of dioxins increases as you move along the food chain of animal origin.

The chemical name of dioxin is 2,3,7,8-tetrachlorodibenzo para dioxin (TCDD) . The name dioxins is often used for the family of structurally and chemically related polychlorinated dibenzo-para-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) . Some dioxin-like polychlorinated biphenyls (PCBs) with similar toxic properties are also referred to as dioxins.419 types of dioxin-related compounds have been identified, but only 30 of them have significant toxicity, with TCDD being the most toxic.

Sources of dioxin pollution

Dioxins are mainly produced by industrial processes, but can also be formed by natural processes such as volcanic eruptions and forest fires. Dioxins are by-products of a number of manufacturing processes, including smelting, chlorine bleaching, and the production of certain herbicides and pesticides.The main culprits for dioxin emissions into the environment are often uncontrolled incinerators (for solid and hospital waste) due to incomplete incineration of waste. Technologies exist that allow controlled incineration of waste with low emissions.

Despite the local formation of dioxins, their distribution in the environment is global. Dioxins can be found anywhere in the world in virtually any environment. The highest levels of these compounds are found in soils, sediment and food, especially dairy products, meat, fish and shellfish.Minor levels are found in plants, water and air.

There are vast stocks of PCB-based industrial waste oils around the world, many of which contain high levels of PCDF. Long-term storage and inappropriate disposal of these materials can result in dioxin releases into the environment and contamination of food for humans and animals. It is not easy to dispose of PCB-based waste without contaminating the environment and human populations. Such materials must be handled as hazardous waste and the best way to dispose of them is by incineration at high temperatures in specially equipped places.

Cases of dioxin contamination

Many countries monitor food for dioxins. This promotes early detection of contamination and often prevents large-scale impacts. In many cases, dioxin contamination occurs through contaminated animal feed, for example, cases of increased dioxin levels in milk or animal feed have been linked to pellets of clay, fat or citrus used in animal feed.

Some cases of dioxin contamination were more significant, with wider consequences for many countries.

In late 2008, Ireland withdrew numerous tons of pork and pork products from the market as dioxin levels were found to be 200 times the safe level in pork samples taken. This led to the withdrawal from sale due to chemical contamination of one of the largest consignments of foodstuffs. Ireland’s risk assessments indicated that there was no public health problem.Contaminated feed was traced to the source of the contamination.

In 1999, high levels of dioxins were found in poultry and eggs from Belgium. Then, dioxin-contaminated animal products (poultry, eggs, pork) were found in several other countries. The source was animal feed contaminated from the illegal disposal of PCB-based industrial waste oils.

In 1976, large quantities of dioxins were released from a chemical plant in Seveso, Italy.A cloud of toxic chemicals, including TCDD, exploded into the air and eventually infected an area of ​​15 square kilometers, which was home to 37,000 people.

Extensive research in the exposed population is ongoing to determine the long-term health effects of this incident.

Extensive research is also underway on the health effects of TCDD due to its presence in some shipments of the herbicide Agent Orange, which was used as a defoliant during the Vietnam War.Its connection with certain types of cancer, as well as diabetes, is still being investigated.

While all countries can be exposed to dioxins, most reported contamination comes from industrialized countries, where food contamination is monitored properly, more hazard awareness and better regulatory tools are in place to detect dioxin-related problems. management.

Several cases of deliberate human poisoning have also been reported.The most significant of these is the case of the poisoning of Viktor Yushchenko, the President of Ukraine, whose face was disfigured by chloracne.

Effects of exposure to dioxins on human health

Short-term exposure to high levels of dioxins in a person can lead to pathological changes in the skin, such as chloracne and focal darkening, as well as changes in liver function. Long-term exposure leads to damage to the immune system, the emerging nervous system, the endocrine system and reproductive functions.

Some types of cancer develop in animals as a result of chronic exposure to dioxins. In 1997 and 2012, the WHO International Agency for Research on Cancer (IARC) assessed TCDD. Based on animal and human epidemiological data, TCDD has been classified by IARC as a “known human carcinogen”. However, TCDD has no effect on genetic material, and there is a level of exposure below which the risk of developing cancer becomes negligible.

Due to the widespread distribution of dioxins, all people are exposed to it and have a certain level of dioxins in the body, which leads to the so-called stress on the body. The current normal background exposure has, on average, no health consequences. However, due to the high toxic potential of this class of compounds, measures must be taken to reduce background exposure.

Sensitive subgroups

The developing fetus is most sensitive to the effects of dioxin.A newborn baby with rapidly developing organ systems may also be more vulnerable to certain exposures. Some people or groups of people may be exposed to higher levels of dioxins due to their diet (for example, people in some parts of the world who eat a lot of fish) or some kind of activity (for example, workers in the pulp and paper industry, incinerators, hazardous waste landfills ).

Prevention and control of dioxin exposure

Proper incineration of contaminated materials is the best available method to prevent and control dioxin exposure.Waste PCB oils can also be disposed of with this method. The combustion process requires high temperatures – over 850 ° C. For the destruction of large quantities of contaminated materials, even higher temperatures are required – 1000 ° and higher.

The best way to prevent or reduce human exposure to dioxins is through source-oriented measures, such as strict control of industrial processes to reduce dioxin emissions as much as possible.This is the responsibility of national governments. The Codex Alimentarius Commission adopted in 2001 a Code of Practice on Source-Based Measures to Reduce Chemical Contamination of Foods (CAC / RCP 49-2001) and in 2006 adopted a Code of Practice to Prevent and Reduce Contamination of Food and Feed dioxins and dioxin-like PCBs (CAC / RCP 62-2006).

More than 90% of human exposure to dioxins occurs through food, mainly meat and dairy products, fish and shellfish.Hence, food protection is critical. In addition to adopting source-oriented measures to reduce dioxin emissions, secondary contamination of food in the food chain must also be avoided. Appropriate controls and practices during primary production, processing, distribution and sale are critical to the production of safe food.

As noted in the examples above, contaminated animal feed is often the root cause of food contamination.

Food contamination monitoring systems are needed to ensure that acceptable levels are not exceeded. Feed and food producers have a responsibility to ensure safe raw materials and safe production processes, and national governments must monitor the safety of the food supply and take measures to protect public health.

National governments must monitor food safety and take action to protect public health.Where contamination is suspected, countries should have contingency plans for the identification, containment and disposal of contaminated feed and food. The exposed population should be monitored in terms of the level of exposure (for example, measuring the level of contaminants in blood or breast milk) and its consequences (for example, establishing clinical observation for signs of ill health).

What should consumers do to reduce the risk of exposure?

Removing fat from meat and consuming low-fat dairy products can reduce exposure to dioxin compounds.A balanced diet (including adequate amounts of fruits, vegetables and grains) also avoids overexposure to dioxin from any one source. This long-term strategy is aimed at reducing the burden on the body and is of particular importance for girls and young women, as it helps to reduce the impact on the developing fetus, and then on the breastfed baby.

What is needed to identify and measure dioxins in the environment and food?

The quantitative chemical analysis of dioxins requires modern methods that are available only in a limited number of laboratories in the world. The cost of such analyzes is very high and depends on the type of sample – from more than $ 1000 for the analysis of a single biological sample to several thousand US dollars for a comprehensive assessment of emissions from an incinerator.

An increasing number of biological screening methods (based on cells or antibodies) are being developed. The use of such methods for examining food samples is not yet sufficiently legalized. Such screening methods will allow more tests to be performed at a lower cost.In the case of a positive screening test, more sophisticated chemical analyzes must be performed to confirm the results.

WHO activities related to dioxins

In 2015, WHO published for the first time estimates of the global burden of foodborne disease. In this context, the consequences of dioxin exposure on reproductive capacity and thyroid function were considered. Looking at these 2 dimensions alone suggests that in some parts of the world such exposure could contribute significantly to the burden of foodborne disease

Reducing dioxin exposure is an important public health goal.With the aim of developing guidance on acceptable exposure levels, WHO has held a series of expert meetings to determine acceptable levels of dioxin intake in humans.

In 2001, the Joint United Nations Food and Agriculture Organization (FAO) / WHO Expert Committee on Food Additives (JACFA) conducted an improved comprehensive risk assessment of exposure to PCDDs, PCDFs and dioxin-like PCBs.

To assess the long-term or short-term health risks associated with these substances, the total or average intake should be estimated over several months, and the acceptable intake should be assessed at least after one month.On a preliminary basis, the experts established an acceptable level of monthly intake of 70 picograms / kg per month. This is the amount of dioxins that can enter the human body throughout his life without detectable health effects.

WHO, in collaboration with FAO through the Codex Alimentarius Commission, has developed a Code of Practice for the Prevention and Reduction of Dioxin and Dioxin-Like PCB Contamination in Food and Feed. This document provides guidance for relevant national and regional authorities in taking preventive action.

WHO is also responsible for the Food Contamination Monitoring and Evaluation Program of the Global Environment Monitoring System. The program, known as GEMS / Food, provides information on levels and trends of contaminants in food through a network of participating laboratories in over 50 countries. Dioxins are included in this program.

WHO also conducts periodic surveys of dioxin levels in human milk, mainly in European countries.These studies assess human exposure to dioxins from all sources. Recent evidence suggests that, over the past two decades, measures introduced in several countries to control dioxin emissions have resulted in significant reductions in exposure to these compounds. Data from developing countries are not sufficient to analyze trends over time.

WHO also conducts periodic surveys of dioxin levels in human milk. These studies assess human exposure to dioxins from all sources.Recent evidence suggests that, over the past two decades, measures introduced in several countries to control dioxin emissions have led to significant reductions in exposure to these compounds.

WHO is continuing this research in collaboration with the United Nations Environment Program (UNEP), in the context of the Stockholm Convention, an international agreement to reduce emissions of certain persistent organic pollutants, including dioxins. The possibility of taking a number of measures to reduce the release of dioxins during combustion and production is being considered.WHO and UNEP are conducting global breast milk surveys, including in many developing countries, to monitor global trends in dioxin pollution and the effectiveness of measures under the Stockholm Convention.

Dioxins are present as a complex mixture in the environment and food. To assess the potential risk of an entire mixture in relation to this group of pollutants, the concept of toxic equivalence is applied.

WHO has established toxic equivalence factors (PTEs) for dioxins and related compounds and is regularly re-evaluating them through expert consultations.The WHO-FTE values ​​have been established, which are used for humans, mammals, birds and fish.

5 thyroid health products

Violation of the full functioning of the thyroid gland is usually associated with a deficiency in the body of nutrients: vitamins and minerals. With minor disruptions in the endocrine system, a person feels constant lethargy, decreased performance, memory impairment.

Further weakening leads to serious pathologies.For example, the formation of goiter, swelling, weight gain or a sharp decrease in body weight with increased appetite, sleep disturbances, irascibility and irritability, high temperature.

Endocrinologists identify several causes of thyroid diseases. Among them, a special place is given to unbalanced nutrition, which leads to a lack of important trace elements in the body. In fact, this organ of the endocrine system “fades away” without receiving a full-fledged “recharge” from the outside. The synthesis of hormones T3 and T4 is sharply reduced, which leads to the development of a whole bunch of chronic pathologies.Various medications are used to treat thyroid diseases.

However, for the prevention of diseases, endocrinologists are advised to periodically take multivitamin complexes with microelements in the form of food supplements.

Vitamins for the thyroid gland

Stable feeding of the endocrine system with hormones is provided by the following vitamin groups:

• Retinol (A) – is responsible for protein biosynthesis. Vitamin A group has a beneficial effect on the immune system, improves the condition of the mucous membranes, bones and teeth. Retinol strengthens nails and hair, relieves puffiness and flabbiness of the skin, and has a good effect on vision. Usually, for prophylaxis, the complex “A” + “E” is attributed to enhance the positive effect of the impact.
• Vitamins B6, B12 – pyridoxine and cobalamin. Vitamin B group accelerates metabolic processes. Increased metabolism prevents the appearance of goiter, obesity, diseases of the cardiovascular and endocrine systems.
• Cholecalciferol (D) – comes from food and is also synthesized in the skin under the influence of a moderate amount of UV rays.Deficiency of this compound leads to the disease hypothyroidism (long-term lack of hormones T3 and T4). Endocrinologists recommend eating foods high in this substance or taking vitamin supplements periodically.
• Antioxidants. This group includes tocopherol (E). Vitamin supplements based on this compound are very popular in cosmetology. They slow down the aging process, relieve skin puffiness, smooth wrinkles. Tocopherol improves the absorption of iodine compounds by cells.He is also credited along with the “A” group for the mutual amplification of the effect. However, doctors advise not to abuse the intake of tocopherol, since its excess with a lack of selenium causes hypothyroidism.

In addition to vitamin complexes, the health of the thyroid gland depends on the presence of trace elements in the body. Important minerals include:

Iron is a trace element that affects the level of hemoglobin in human blood. The normal iron content helps to steadily transport oxygen to the organs and tissues of the body.As with antioxidants “E”, excess or lack of the mineral leads to problems with the endocrine system, in particular, causes hyperthyroidism.

Selenium is a trace element, without which the production of hormones T3 and T4 is impossible. This mineral protects organs from oxidation, improves metabolism, controls growth and supports reproductive function in men. Lack of selenium leads to diseases such as Hashimoto’s thyroiditis – immune problems.

Iodine – without this trace element, the endocrine system will not be able to fully function.The mineral participates in metabolic processes and in the synthesis of more than 100 enzymes, regulates the body’s water-salt balance. The lack of an element leads to the formation of goiter and the development of hypothyroidism, impairs intellectual abilities. An excess of iodine compounds leads to poisoning of the body.

Products for thyroid disease

To reduce the risk of endocrine system pathologies, doctors recommend a diet with substances important for thyroid health. For the prevention of diseases and the treatment of the organ, it is necessary to include in the diet:

• Feijoa and persimmon – these iodine-containing fruits can be eaten at any time of the year.Fruits are also rich in sodium, magnesium and iron. In addition, persimmon and feijoa are a storehouse of vitamin compounds A, C and P.
• Fresh seafood includes mussels, crabs, fish, lobsters, shrimps, squids, etc. The same iodine products as persimmon and feijoa. Contains zinc, fatty acids, phosphorus, protein, B12. People who love seafood have strong immunity, their endocrine system is regularly fueled by important hormones.
• Seaweed is the primary source of iodine compounds.What prevention of endocrine diseases would do without this ingredient? It is enough to eat 70-100 grams of seaweed per day for the body to stably produce thyroid hormones. It also contains phosphorus, magnesium, silicon and a number of other beneficial minerals.
• Red fish – salmon, trout, pink salmon, salmon and any red meat contain tyrosine. This substance helps to synthesize the necessary hormones. If there is enough red fish in the diet, then calcium, omega-3 fatty acids, vitamin D, phosphorus enter the body.In addition, fish liver is a source of selenium.
• Spinach, onions – strengthen the immune system, and are also natural antioxidants. In addition, spinach contains a unique set of trace minerals important for endocrine health. These are phosphorus, zinc, iodide compounds, sodium, manganese and others.

It should also be noted the benefits of apples, berries and nuts for all body systems. Pine and walnuts are rich in iodine compounds. Apples and blueberries contain antioxidant substances that protect cells from the harmful effects of free radicals.

Harmful products

Endocrinologists don’t just talk about a balanced and correct diet. According to WHO statistics, over 670 million people in the world suffer from various forms of hyperthyroidism, and more than 1.7 billion are at risk of contracting endocrine system pathologies. Almost 70% of this number love and eat junk food every day. This is a reason – to think!

What kind of food should be given up in case of problems with the thyroid gland:

• Sugar. All popular and cheap food contains incredible amounts of sugar.These are sweet and carbonated drinks, pastries, cakes, sweets and more. There is more harm than good from such food. Autoimmune diseases and diabetes mellitus are caused by uncontrolled consumption of sweets. With such a diet, the level of hormones decreases, almost all systems are overloaded, the body does not perceive insulin.
• Fried and fatty foods contain unhealthy trans fats. If you love eating fried foods, try adding more greens, fish, and seaweed to your diet.In case of obvious problems with the endocrine system, the consumption of fried foods should be reduced and even excluded, because it reduces the production of hormones T3 and T4.
• Gluten is a substance (gluten) found in cereals and causes great harm to a healthy body. Foods high in gluten cause autoimmune disorders such as Addison’s disease, type 1 diabetes, rheumatoid arthritis, and hypothyroidism. Gluten is found in baked goods, premium wheat bread, etc.
• Semi-finished products, fast food, preservatives – all these foods cannot be called useful for human health and the endocrine system.