Does the thyroid regulate body temperature. Hypothyroidism and Body Temperature Regulation: Understanding the Thyroid’s Role
How does the thyroid gland regulate body temperature. What are the effects of hypothyroidism on internal temperature. Can external temperatures impact thyroid function. How is hypothyroidism diagnosed and treated.
The Thyroid Gland’s Role in Temperature Regulation
The thyroid gland plays a crucial role in regulating body temperature. This small, butterfly-shaped gland located in the neck produces hormones that are essential for maintaining our internal thermostat. But how exactly does the thyroid contribute to temperature control?
Thyroid hormones, primarily thyroxine (T4) and triiodothyronine (T3), influence the body’s metabolic rate. This, in turn, affects heat production and energy expenditure. When thyroid function is normal, these hormones help maintain a stable core body temperature of around 98.6°F (37°C).
Thyroid Hormones and Metabolism
Thyroid hormones increase the basal metabolic rate, which is the amount of energy your body uses at rest. This process generates heat as a byproduct. In essence, the thyroid acts like a thermostat, adjusting metabolism to produce more or less heat as needed to maintain optimal body temperature.
Hypothyroidism and Its Impact on Internal Temperature
Hypothyroidism, a condition characterized by an underactive thyroid gland, can significantly affect the body’s ability to regulate temperature. When the thyroid doesn’t produce enough hormones, it can lead to a variety of symptoms, including an increased sensitivity to cold.
Cold Sensitivity in Hypothyroidism
Why do people with hypothyroidism often feel cold? Dr. Harris L. Wasser, an endocrinologist at Los Robles Regional Medical Center, explains: “With hypothyroidism, metabolism slows, body temperature drops, cutaneous (skin) vasoconstriction occurs, and the patient may feel cold even in a warm environment.”
This increased sensitivity to cold is due to the decreased metabolic rate and reduced heat production associated with low thyroid hormone levels. Additionally, hypothyroidism can affect the body’s ability to regulate blood flow to the extremities, leading to cold hands and feet.
Other Temperature-Related Symptoms
- Lowered core body temperature
- Difficulty warming up after exposure to cold
- Intolerance to cold environments
- Reduced sweating
External Temperature Effects on Thyroid Function
While the thyroid regulates internal temperature, can external temperatures impact thyroid function? Research suggests that extreme or chronic cold exposure may influence thyroid activity.
The Greenland Study
A study published in the European Journal of Endocrinology in 2012 examined the impact of chronic cold exposure on thyroid activity among residents of Greenland. The results showed increased thyroid hormone consumption across both indigenous Inuits and non-Inuits living in the region.
Cold Adaptation and Thyroid Function
Dr. Wasser notes that extreme cold exposure may lead to increased thyroid production and turnover. However, he emphasizes that this is primarily observed in regions with severe, chronic cold, such as the Arctic. For most people, typical exposure to cold external temperatures produces minimal to no change in thyroid levels.
Diagnosing Hypothyroidism: Beyond Feeling Cold
While feeling cold is a common symptom of hypothyroidism, it’s not sufficient for diagnosis on its own. How is hypothyroidism properly diagnosed?
Key Diagnostic Steps
- Physical examination of the thyroid gland
- Assessment of other physical symptoms (e.g., brittle nails, coarse facial features)
- Blood tests to measure thyroid hormone levels
The primary diagnostic tool for hypothyroidism is a blood test measuring levels of thyroid-stimulating hormone (TSH). Higher than normal TSH levels often indicate hypothyroidism, as the pituitary gland produces more TSH to stimulate the underactive thyroid.
Treatment Options for Hypothyroidism
Once diagnosed, how is hypothyroidism treated? The primary treatment for hypothyroidism is thyroid hormone replacement therapy.
Thyroid Hormone Replacement
Dr. Frederick Singer, an endocrinologist at the John Wayne Cancer Institute, explains that thyroid hormone treatment can help reverse low body temperature and other hypothyroidism symptoms. The most common medication used is levothyroxine, a synthetic form of the T4 hormone.
Treatment Goals
- Restore normal thyroid hormone levels
- Alleviate symptoms, including temperature sensitivity
- Prevent long-term complications of untreated hypothyroidism
With proper treatment and adherence to the prescribed medication regimen, most people with hypothyroidism can effectively manage their condition and maintain normal thyroid function.
Managing Hypothyroidism: Beyond Medication
While medication is the cornerstone of hypothyroidism treatment, lifestyle factors can also play a role in managing the condition and its symptoms.
Diet and Nutrition
Can dietary changes help manage hypothyroidism? While there’s no specific “hypothyroidism diet,” certain nutritional strategies may support thyroid health:
- Ensure adequate iodine intake (but avoid excess)
- Consume selenium-rich foods (e.g., Brazil nuts, fish)
- Limit goitrogenic foods that may interfere with thyroid function
- Maintain a balanced diet rich in fruits, vegetables, and lean proteins
Exercise and Physical Activity
Regular exercise can help boost metabolism, improve energy levels, and support overall well-being in people with hypothyroidism. However, it’s important to start slowly and gradually increase intensity, especially if fatigue is a significant symptom.
Stress Management
Chronic stress can potentially exacerbate hypothyroidism symptoms. Implementing stress-reduction techniques such as meditation, yoga, or deep breathing exercises may be beneficial.
Hypothyroidism and Weight Management
Weight gain is a common concern for people with hypothyroidism. The condition can slow metabolism, making weight loss more challenging. However, with proper treatment and lifestyle modifications, maintaining a healthy weight is possible.
Weight Loss Strategies for Hypothyroidism
- Optimize thyroid hormone replacement therapy
- Focus on nutrient-dense, whole foods
- Incorporate regular physical activity
- Monitor portion sizes
- Stay hydrated
- Get adequate sleep
It’s important to work closely with a healthcare provider to develop a personalized weight management plan that takes into account your specific thyroid function and overall health status.
The Evolution of Temperature Regulation in Humans
The ability to maintain a constant body temperature sets humans apart from many other species. This thermoregulatory capacity has evolved over millions of years, allowing us to adapt to various climates without the need for hibernation or migration.
The Role of the Thyroid in Human Evolution
The thyroid gland has played a crucial role in this evolutionary process. Its ability to regulate metabolism and heat production has contributed significantly to our species’ adaptability and survival in diverse environments.
Comparative Thermoregulation
How does human thermoregulation compare to that of other animals? Unlike many mammals and birds, humans can maintain a relatively stable body temperature across a wide range of external conditions. This is due to a combination of physiological mechanisms, including:
- Sweat production for cooling
- Shivering for heat generation
- Vasodilation and vasoconstriction for blood flow regulation
- Hormonal regulation, particularly by the thyroid
These adaptations have allowed humans to thrive in environments ranging from tropical rainforests to arctic tundras.
Future Directions in Thyroid Research and Treatment
As our understanding of thyroid function and its role in temperature regulation continues to evolve, what does the future hold for thyroid research and treatment?
Emerging Research Areas
- Genetic factors influencing thyroid function and temperature sensitivity
- The impact of environmental toxins on thyroid health
- The role of the gut microbiome in thyroid hormone metabolism
- Personalized medicine approaches for thyroid disorders
Advancements in Treatment
Researchers are exploring new treatment modalities for thyroid disorders, including:
- Novel drug delivery systems for thyroid hormone replacement
- Targeted therapies for autoimmune thyroid conditions
- Regenerative medicine approaches to restore thyroid function
- Improved diagnostic tools for early detection of thyroid disorders
These advancements hold promise for more effective and personalized management of thyroid conditions, including those affecting temperature regulation.
The Broader Impact of Thyroid Health on Overall Well-being
While temperature regulation is a crucial function of the thyroid, its influence extends far beyond thermoregulation. The thyroid gland plays a vital role in numerous bodily processes, affecting overall health and well-being.
Thyroid Function and Cognitive Health
Research has shown a connection between thyroid function and cognitive performance. Both hypothyroidism and hyperthyroidism can impact memory, concentration, and mood. Proper thyroid hormone balance is essential for optimal brain function.
Cardiovascular Health and the Thyroid
Thyroid hormones influence heart rate, blood pressure, and cholesterol levels. Hypothyroidism can increase the risk of cardiovascular disease, while hyperthyroidism can lead to heart rhythm abnormalities. Maintaining healthy thyroid function is crucial for heart health.
Reproductive Health and Fertility
The thyroid plays a significant role in reproductive health for both men and women. Thyroid disorders can affect menstrual cycles, ovulation, and sperm production. Proper thyroid function is particularly important during pregnancy for fetal development.
Bone Health and Thyroid Function
Thyroid hormones are involved in bone metabolism. Both hypothyroidism and hyperthyroidism can affect bone density, potentially increasing the risk of osteoporosis. Regular monitoring of thyroid function is important for maintaining strong, healthy bones.
Living Well with Thyroid Disorders
Managing a thyroid condition requires more than just medication. It involves a holistic approach to health and well-being. Here are some strategies for living well with thyroid disorders:
Regular Monitoring and Follow-up
Consistent check-ups and thyroid function tests are crucial for ensuring optimal thyroid hormone levels. Work closely with your healthcare provider to adjust treatment as needed.
Lifestyle Modifications
- Prioritize sleep: Aim for 7-9 hours of quality sleep per night
- Manage stress: Incorporate relaxation techniques into your daily routine
- Stay active: Regular exercise can help boost energy and mood
- Eat a balanced diet: Focus on nutrient-dense foods that support thyroid health
Support and Education
Joining support groups or seeking out educational resources can provide valuable information and emotional support. Understanding your condition empowers you to take an active role in your health management.
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Complementary Therapies
Some people find benefit in complementary therapies such as acupuncture or herbal supplements. Always consult with your healthcare provider before starting any new treatments to ensure they don’t interfere with your thyroid medication.
By taking a comprehensive approach to thyroid health, individuals can effectively manage their condition and maintain overall well-being, including proper temperature regulation.
Hypothyroidism and Your Internal Temperature
How Hypothyroidism Affects Your Internal Temperature
Hypothyroidism symptoms include constipation, fatigue, joint or muscle pain, and even depression. The condition can also cause an increased sensitivity to cold temperatures.
“With hypothyroidism, metabolism slows, body temperature drops, cutaneous (skin) vasoconstriction occurs, and the patient may feel cold even in a warm environment,” says Harris L. Wasser, MD, an endocrinologist at Los Robles Regional Medical Center in Thousand Oaks, Calif.
That said, feeling cold in the hands and feet isn’t enough to make a hypothyroidism diagnosis. These sensations may also be symptoms of a wide range of other conditions, including anemia and impaired circulation.
Hypothyroidism and External Temperature
While internal processes affect the body’s use of thyroid hormones, severe outside temperatures can affect those with hypothyroidism as well.
A study published in the European Journal of Endocrinology in 2012 looked at the impact of the chronic cold in Greenland on thyroid activity among its residents, both indigenous Inuits and non-Inuits. Results showed increased thyroid hormone consumption across the board.
Dr. Wasser cautions, however, that this may be an unusual situation. “In extreme, chronic, or severe cold exposure — in regions such as Arctic or northern Alaska — cold adaptation is reported to increase thyroid production and turnover,” he says. But, he notes, “exposure to cold external temperatures in general produces minimum to no change in thyroid levels.”
Confirming a Hypothyroidism Diagnosis
While feeling cold isn’t enough to diagnose hypothyroidism alone, it may be a sign that it’s time to test for it. Talk to your doctor and ask about having your thyroid function checked. Your doctor should examine your thyroid gland and look for other physical clues, such as brittle nails and hair, swelling of the arms or legs, and coarse facial features.
A simple blood test can measure levels of the thyroid hormone TSH — higher than normal TSH levels are most often due to hypothyroidism.
If a positive diagnosis is made, the next step is to undergo thyroid hormone treatment, which can help to reverse a low body temperature and any other hypothyroidism symptoms, says Frederick Singer, MD, an endocrinologist and director of the endocrinology and bone disease program at the John Wayne Cancer Institute at Saint John’s Health Center in Santa Monica, Calif. Then, by following your prescribed treatment plan, you can help ensure that thyroid levels return to normal.
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How Thyroid Maintains Body Temperature?
How Thyroid Maintains Body Temperature?
Created On
Dec 07 2020
Last Updated
Feb 21 2023
This summary includes research published in peer-reviewed journals including Frontiers in Bioscience, Archives of Internal Medicine, Physiological Reviews, and more.
We humans differ from animals and birds in a unique way: we can maintain a constant body temperature and don’t require hibernation or migration to warmer climates.
As simple as this may sound, maintaining body temperature has taken millions of years to evolve.
Beyond a certain amount of heat generated from metabolism, this requires a system that can generate additional heat in order to raise body temperature (e.
g., to 37° C for humans, 42° C for birds).
Fighting Cold
During cold, as outside temperature drops, blood vessels shrink to reduce heat loss and people curl up like a sphere, to minimize the exposed area of the body (sphere has minimum surface area for a given size).
In parallel, the body starts generating heat. At first through shivering, but then the baseline metabolic rate increases. Over time, the brown fat deposited around vital organs such as kidney, spinal cord and blood vessels starts to generate enough heat to raise the body temperature.
What if the outside temperature is too high?
We have developed unique processes to dissipate heat and lower the body temperature. Sweating to cool down, and slowing down of certain biological processes to reduce heat generated in the body are just few examples. (That’s one reason why people eat spicy food in hot climates, because it increases sweating, which cools the body.)
Metabolic Rate
The baseline metabolic rate, or BMR, is the lowest amount of energy necessary to stay alive.
This would ideally be the minimum energy our body needs.
It is measured at rest, after a meal, and at ambient temperature when no work is needed to heat or cool the body in response to outside temperature fluctuations.
Since we often live indoor at 20-25° C, our body is constantly burning stored fat to keep the temperature at 37° C.
In animals that live in cold environments, more body heat is necessary to maintain the temperature. It comes from a higher baseline metabolic rate and constant heat generated from the stored fat.
The baseline metabolic rate—sometimes also called, resting energy expenditure—depends on size, genetics, and many other factors including age, pregnancy, and gender.
Role of Thyroid Hormones
Thyroid is one of the main knobs to maintain a tightly controlled temperature around a 37° C (or 98.6° F). Even birds and other mammals use thyroid hormones to balance their body temperature.
During cold, thyroid hormones, T4 and T3 will stimulate the body to generate more heat.
In hot weather, when outside temperature rises above our body temperature, the release of TSH slows down. T4 and T3 already circulating in the blood lose an iodine atom and convert into non-active forms, e.g., T4 into reverse T3 (rT3).
What happens if the system malfunctions and the body continues to produce thyroid hormones?
Hyperthyroidism is such a condition when excess thyroid hormone, T4, circulates in the blood. As a consequence, the body constantly struggles to lower the temperature. This results in common symptoms of fatigue, high sensitivity of heat, irritation, and weight loss.
On the other hand, in hypothyroidism, our body can not supply enough thyroid hormones to maintain the temperature. A typical symptom is continuous feeling of cold.
Initially, TSH levels rise (or drop) to maintain sufficient T4 and T3 levels. However, beyond a certain level when TSH levels saturate (or bottom out), the system malfunctions, resulting in a thyroid disorder.
Thyroid and Body Fat
The so called brown adipose tissue—the brown fat distributed around key organs such as liver, heart, kidneys, etc.
—is one of the key players in maintaining body temperature. On exposure to cold, these BAT cells generate the necessary heat to raise the temperature.
In hypermetabolic state—in hyperthyroidism—resting energy spending increases, people lose weight, their cholesterol levels drop, brown and white fat burning increases, and a higher blood sugar appears. These processes reverse in case of hypothyroidism.
Technical info – how a signal of feeling cold, translates into heat generation in the body?
As soon as the skin senses cold, blood vessels shrink, and the sympathetic nerves send signal to hypothalamus. This causes shivering, and the brown fat surrounding blood vessels and key organs receive signal to activate their adrenaline receptors (norepinephrine). This results in fat burning (lipolysis) to release heat in the body. Thyroid hormones and the uncoupling protein (UCP1) rapidly activate by lipolysis and the cell mitochondria oxidation results in heat generation.
Thyroid and Diabetes
Have you noticed the feeling of slump after a meal?
That’s because carbohydrate metabolism and the resulting insulin acts as a switch to activate the enzyme responsible for body heat generation.
Fasting slows down the supply of thyroid hormones to avoid any fat burning in the body—a behavior similar to hypothyroidism.
In diabetes, the insulin resistance affects body’s ability to stay warm through heat generation from the process of burning brown fat tissues.
In animals that have thyroid dysfunction—and can not properly control the process of fat burning to generate heat—continuous eating is essential to keep them warm.
During extreme starvation, the body shuts down this heat producing mechanism. Similar slow down occurs in hibernation, which is also mediated by thyroid hormones.
Thyroid and Weight Loss
Thyroid hormones play a key role in controlling metabolism together with brain, white fat, brown fat, skeleton muscles, liver, and pancreas.
That’s why they are considered potential paths to solve the metabolic disorders related to obesity, diabetes, and high cholesterol. A thyroid test is one of the first step to understand the underlying issues.
Low thyroid hormone levels are also associated with retaining water in the body. On treatment, release of this excess water results in weight loss (amount of fat generally remains the same).
Studies suggest hyperthyroidism increases craving for carbohydrates which returns to normal after treatment of high thyroid hormones levels.
Interestingly, T3 is about ten-times more active than T4 in the body. That’s why it is seems to be more effective in weight loss and lowering cholesterol. However, no effect on insulin or cardiovascular health occurs.
A tiny gland in the throat has developed as a vital organ to maintain such a complex system of temperature control is truly an amazing feat of evolution.
References:
Thyroid Hormone Regulation of Metabolism by Mullur et.
al., Physiological Reviews, Vol 92, Apr 2014.Physiological importance and control of non-shivering facultative thermogenesis by J. Enrique Silva, Frontiers in Bioscience, S3, Jan 2011.
Relations of Thyroid Function to Body Weight: Cross-Sectional and Longitudinal Observations in a Community-Based Sample by Fox et. al., Archives of Internal Medicine, Vol 168, Mar 2008.
Mechanisms of thyroid hormone action by Gregory A Brent, The Journal of Clinical Investigation, Vol 122, Sep 2012.
al., Physiological Reviews, Vol 92, Apr 2014.An unhealthy thyroid gland disrupts thermoregulation – Gazeta.Ru
If you are cold – check your thyroid gland – Gazeta.Ru
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Scientists have found out why people with thyroid disorders are more sensitive to ambient temperature.
Those who have an overactive or underactive thyroid gland often feel that their body temperature is above or below normal. This phenomenon is well known to physicians, but until now it has been associated exclusively with the influence of thyroid hormones on the intensity of metabolism in cells.
Swedish scientists have found that the main cause of thermoregulation disorders lies not at all in a change in metabolism, but in the effect of thyroid hormones on blood vessels.
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Hormones are signal molecules that are produced in the body in small quantities and are carried with the bloodstream to all organs and cells. When they interact with receptors, the signal is greatly amplified and converted into a physiological one. There can be different receptors for the same hormone in different organs. For example, the thyroid hormone receptor TR-α1 is most active in cardiac and skeletal muscle.
Scientists from the Karolinska Institute in Sweden have obtained a mutant line of laboratory mice in which TR-α1 was “broken”. The mutant rodents generated large amounts of heat as metabolism increased dramatically in a specialized tissue called brown fat. Brown adipose tissue is present in all mammals. It is especially developed in hibernating animals. People also have it: in newborns it is 5% of the total body weight.
The main function of brown fat is to give warmth “from the inside”, to warm.
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So, as Swedish scientists found out, despite the increased metabolic activity of brown adipose tissue, the body temperature of mutant rodents with a broken thyroid hormone receptor did not increase. It turned out that, among other things, when the receptor was broken, blood vessels lost their ability to narrow or expand under the influence of signaling molecules of the nervous system, such as acetylcholine.
When scientists measured the temperature of various parts of the body of mutant mice using infrared thermography, they noticed that the heat generated by brown fat dissipated through the surface of the body, and was not stored, as is the case with normal functioning of the body, and was not used for internal heating. Especially a lot of heat “leaked” through the tail. By injecting a specially selected vasoconstrictor into the tail artery, it was possible to prevent heat loss and, as a result, normalize the activity of brown adipose tissue.
The findings, according to scientists, explain why patients with thyroid diseases are so sensitive to temperature changes.
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This is the first study of its kind to discover the molecular mechanisms of thyroid hormone-mediated thermoregulation and show the relationship between processes occurring in adipose tissue and the cardiovascular system.
It also became clear that the unbalanced work of blood vessels nullifies all the body’s efforts aimed at heating. Mice that produce excess heat and are unable to store it get cold. People are in a better position. Unlike rodents, they can wrap themselves in a warm sweater or turn on the air conditioner for heating. Nevertheless, in the long term, these studies should be considered as the first stage in the search for means of correcting vascular dysfunction. Results of work published in the scientific journal PNAS .
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Body temperature depends on the level of thyroid hormones
July 2, 2013 about 09
Kotikovich Yu.
S.
Keywords:
hypothyroidism,
adipose tissue,
blood vessels,
thyroid hormones,
thyroid gland
Specialties:
Endocrinology
Internal Medicine
90 004 Summary
Results of a study by Swedish scientists on laboratory animals
In a new study, Swedish scientists from the Karolinska Institutet, Stockholm, have determined how thyroid hormones (thyroid gland) affect blood vessels and thereby determine body temperature. They believe the findings will help explain why thyroid patients are more sensitive to ambient temperature than healthy people. The results of the study were published in the journal Proceedings of the National Academy of Sciences.
Thyroid hormones are the main regulators of thermogenesis, affecting both peripheral organs and central autonomous mechanisms. It is known that with hyperfunction of the thyroid gland, a person experiences heat intolerance and a feeling of constant heat, his skin has an elevated temperature, and with hypofunction, on the contrary, low temperature intolerance and a decrease in body temperature are characteristic. In previous studies, scientists have found out how thyroid hormones affect metabolism at the cellular level.
In this work, the state of thermogenesis in laboratory mice with receptor-mediated hypothyroidism resulting from a mutation of one of the thyroid hormone receptors, TR-alpha 1, was studied. The researchers note that this receptor is expressed only in some tissues, and with the studied mutation, these tissues (central nervous system, bone and muscle tissue) become immune to the action of thyroid hormones. The author of the study, Dr. Amy Warner, noted that this mutation greatly facilitates the process of studying certain aspects of thyroid dysfunction, while the state of most organs and systems remains normal. She recalled that thyroid hormones determine the level of basal metabolism, affecting the rate of cellular metabolism, therefore, with hypothyroidism, all processes should slow down.
However, in previous studies, scientists noted that mice with a similar mutation had an accelerated metabolism due to the production of energy necessary for the synthesis of heat from their brown adipose tissue.
In this paper, after analyzing the infrared radiation of mice, the researchers were surprised to find that mice lose a significant amount of energy through their tails – a mutation in the receptor led to the fact that the organisms of these animals were unable to adequately regulate the narrowing of blood vessels.
With the help of the tail, healthy mice regulate body temperature by changing the lumen of blood vessels. When this regulation is not possible in mice, heat synthesis from brown adipose tissue is activated, which, in turn, increases the need for energy and accelerates metabolism, despite hypothyroidism. When midodrine, a drug that causes blood vessels to constrict, was administered to mice, heat loss through the tail was reduced, and mice were able to maintain body temperature without activating heat production from brown adipose tissue. Their oxygen and nutrient requirements also returned to normal, which supports the assumption that the increased energy expenditure is caused by the mobilization of adipose tissue, and not by mutation of the receptors.