What are the three major nutrient groups that provide energy. How do carbohydrates, proteins, and fats contribute to our body’s energy needs. What is the recommended daily intake of these nutrients. How do these nutrients affect our health and well-being.

The Three Major Energy-Providing Nutrients: An Overview

Our bodies require energy to function properly, and this energy comes primarily from three major nutrient groups: carbohydrates, proteins, and fats. Each of these nutrients plays a crucial role in providing the fuel our bodies need for various processes, from basic cellular functions to complex physical activities.

Let’s explore the unique characteristics and contributions of each nutrient:

• Carbohydrates: The body’s preferred energy source
• Proteins: Essential for growth, development, and energy when carbohydrates are scarce
• Fats: Concentrated energy source and vital for various bodily functions

Carbohydrates: The Body’s Primary Energy Source

Carbohydrates are the body’s main and preferred source of energy. They come in various forms, including sugars, starches, and fibers. But why are carbohydrates so important for our energy needs?

Types of Carbohydrates

Carbohydrates can be categorized into two main types:

1. Simple carbohydrates (sugars): These include glucose, fructose, and sucrose, which are quickly absorbed and provide rapid energy.
2. Complex carbohydrates (starches and fibers): These take longer to digest and provide sustained energy over time.

What happens when we don’t consume enough carbohydrates? In the absence of sufficient carbohydrates, the body turns to proteins as an energy source. This is not ideal, as proteins are better utilized for growth, development, and regulatory functions.

The Role of Fiber

While fiber is a type of carbohydrate, it doesn’t provide direct energy. Instead, it offers other essential benefits:

• Promotes normal digestion
• Aids in waste elimination
• Provides a feeling of fullness
• Slows the rate at which the stomach empties

Carbohydrate-Related Health Conditions

Understanding carbohydrates is crucial for managing certain health conditions. What are some health issues related to carbohydrate metabolism?

1. Diabetes Mellitus: This condition occurs when the body doesn’t produce enough insulin or fails to use it correctly, leading to high blood glucose levels.
2. Lactose Intolerance: This is caused by a lack of the enzyme lactase, which is needed to break down lactose in dairy products.

Proteins: Building Blocks and Emergency Energy

Proteins are unique among the energy-providing nutrients due to their composition and primary functions. What makes proteins different from carbohydrates and fats?

Composition and Structure of Proteins

Proteins are composed of carbon, hydrogen, oxygen, and nitrogen. The presence of nitrogen sets them apart from carbohydrates and fats. The building blocks of proteins are amino acids, with nine of them being essential, meaning our bodies cannot produce them and must obtain them from food sources.

Protein Quality and Sources

The quality of a protein is determined by its ability to provide all nine essential amino acids in the necessary proportions. Which foods provide high-quality proteins?

• Animal sources: eggs, dairy, meat, poultry, and fish
• Vegetable source: soy

These protein sources are considered complete proteins as they contain all essential amino acids.

Protein Functions in the Body

While proteins can provide energy, their primary functions in the body include:

1. Maintaining acid-base balance
2. Carrying vital substances throughout the body
3. Supporting growth and development
4. Serving as a backup energy source when carbohydrates and fats are lacking

Recommended Protein Intake

How much protein should we consume daily? The current recommended daily intake for adults is 0.8 grams of protein per kilogram of body weight. However, children and certain adults may require more, depending on their activity level and health status.

Fats: Concentrated Energy and Essential Functions

Fats, while often vilified, play crucial roles in our body’s functioning. What are the essential functions of fats in our diet?

Composition and Types of Fats

Fats are composed of carbon, hydrogen, and oxygen. They can be categorized into three main types:

1. Saturated fats: Usually solid at room temperature (e.g., butter, ghee, lard)
2. Monounsaturated fats: Liquid at room temperature (e.g., olive oil, avocado oil)
3. Polyunsaturated fats: Liquid at room temperature (e.g., corn oil, soybean oil, fish oil)

Functions of Fats in the Body

Fats serve several important functions:

• Provide concentrated energy (9 calories per gram, compared to 4 calories per gram for carbohydrates and proteins)
• Help form cell membranes
• Maintain body temperature
• Protect nerves
• Aid in the absorption and storage of fat-soluble vitamins (A, D, E, and K)

Recommended Fat Intake

What is the recommended daily intake of fats? Nutritionists suggest that 20-35% of your daily calories should come from fats, primarily unsaturated fats. It’s important to limit saturated fat intake, as excessive consumption can lead to heart disease.

Energy Balance: Consumption vs. Expenditure

Understanding the relationship between energy consumption and body weight is crucial for maintaining a healthy lifestyle. How does the amount of energy we consume affect our body weight?

Basal Metabolic Rate (BMR)

The basal metabolic rate (BMR) is the amount of energy your body uses to maintain basic life functions while at rest. This accounts for about 60-75% of the total energy expenditure for most people. Factors that influence BMR include:

• Age
• Gender
• Body composition
• Genetics
• Hormonal factors

Energy Balance Equation

The relationship between energy intake and body weight can be summarized in a simple equation:

Energy Balance = Energy Intake – Energy Expenditure

When energy intake equals energy expenditure, body weight remains stable. If energy intake exceeds expenditure, weight gain occurs. Conversely, if energy expenditure exceeds intake, weight loss occurs.

Nutritional Considerations for Optimal Health

Achieving a balanced diet that provides adequate energy while supporting overall health requires careful consideration of nutrient intake. What are some key nutritional considerations for optimal health?

Balancing Macronutrients

While individual needs may vary, general recommendations for macronutrient intake are:

• Carbohydrates: 45-65% of total daily calories
• Proteins: 10-35% of total daily calories
• Fats: 20-35% of total daily calories

Choosing Quality Nutrient Sources

The quality of nutrient sources is just as important as the quantity. Some guidelines for choosing quality nutrient sources include:

1. Opt for complex carbohydrates over simple sugars
2. Choose lean protein sources and plant-based proteins
3. Prioritize unsaturated fats over saturated fats
4. Include a variety of fruits, vegetables, whole grains, and legumes in your diet

The Impact of Nutrient Balance on Health and Well-being

Maintaining a proper balance of energy-providing nutrients is crucial for overall health and well-being. How does nutrient balance affect our health?

Short-term Effects of Nutrient Imbalance

Improper nutrient balance can lead to various short-term effects:

• Fatigue and lack of energy
• Mood swings and irritability
• Difficulty concentrating
• Digestive issues

Long-term Health Implications

Chronic nutrient imbalance can contribute to various health issues:

1. Obesity and related complications
2. Type 2 diabetes
3. Cardiovascular diseases
4. Certain types of cancer
5. Osteoporosis

By understanding the roles of carbohydrates, proteins, and fats in providing energy and supporting bodily functions, we can make informed decisions about our diet. Balancing these nutrients according to individual needs and activity levels is key to maintaining optimal health and preventing nutrition-related diseases. Remember, while general guidelines exist, consulting with a healthcare professional or registered dietitian can help tailor nutritional recommendations to your specific needs and health goals.

Chapter 10: Nutrients that Provide Energy (Carbohydrates, Fats, and Proteins) – HLT 111 – Health and the Young Child – Textbook

Chapter 10: Nutrients that Provide Energy (Carbohydrates, Fats, and Proteins)

Chapter objectives

At the conclusion of this chapter students will be able to

1. Identify the three major nutrient groups and their energy contributions
2. Define the concepts of basal metabolic rate
3.  Describe the relationship between amount of energy consumed and body weight.
4. Describe simple sugars and complex carbohydrates as sources of energy
5. Describe proteins as energy source; explain complete and incomplete proteins
6. Describe unsaturated, monosaturated and poly saturated fats as sources of energy.

Overview

Carbohydrates

Carbohydrates are one of the six major nutrients and the main source of energy. Examples of carbohydrates include sugars, starch, and fiber in the diet. The body’s top priority is to provide enough energy for all cellular activities needed to sustain life. Carbohydrates are the preferred source of energy. If the diet does not provide adequate carbohydrates the body will draw mainly upon proteins for its energy needs.

By eating  adequate amounts of carbohydrates, proteins will be spared to be used for growth, development and regulatory functions of the body. If the diet is too low in carbohydrates, the body cannot break down fats completely, and incomplete fat break down products called ketones are produced and this may lead to Ketosis, a condition frequently encountered in diabetes mellitus, though in this case the cause is failure of the body to utilize carbohydrates rather that inadequate intake.

Fibers are carbohydrates which provide bulk in the diet. Fiber also helps to promote normal digestion and elimination of waste materials. Fibers also provide a feeling fullness by slowing the rate at which the stomach empties.

When the body does not make enough insulin or fails to use insulin correctly, glucose builds up in the bloodstream, a condition called diabetes mellitus. Another condition related to carbohydrate metabolism is called lactose intolerance.  This condition is caused by a lack of the digestive enzyme lactase, which is needed to break down lactose.  People who are lactose intolerant may experience gas, cramping, nausea and diarrhea when they consume dairy products.

Proteins

Protein is an energy-yielding nutrient composed of carbon, hydrogen, oxygen, and nitrogen.

Proteins differs from carbohydrates and fats because of the presence of nitrogen. They are the  building blocks of all protein molecules are amino acids.  Protein is vital to the optimal growth and development of kids. Proteins account for 50% of the dry weight of the human body. Unlike lipids and carbohydrates, proteins are not stored, so they must be consumed daily. Current recommended daily intake for adults is 0.8 grams of protein per kg of body weight (more is needed for children).

The quality of a protein is determined by its ability to provide the 9 essential amino acids.   Proteins from animal sources (eggs, dairy, meat, poultry, and fish) and one vegetable protein (soy) are all considered high-quality because they contain all of the essential amino acids in the necessary proportions. The function proteins includes,

• Maintain acid-base balance
• Maintenance of the correct level of acidity of a body fluid
• Proteins in the blood act as chemical buffers (counteract an excess of acid or base in a fluid)
• Carry vital substances
• Transport lipoproteins (protein linked with fat), iron, and other nutrients, as well as oxygen, chromosomes, and other bundles of protein to other parts of cells
• Provide energy
• Provides the cells with the energy they need to exist

If carbs and fats are lacking, the body uses protein as an energy source

Fats

Fats are made of carbon, hydrogen, and oxygen. Fats supply your body with energy, form your cells, maintain body temperature, and protect your nerves.   A nutrient that provides energy and helps the body store and use vitamins is a fat.  Unsaturated Fats have at least one unsaturated bond in a place where hydrogen can be added to the molecule. Unsaturated fats are usually liquid at room temperature (corn oil, soybean oil, peanut oil).

Unsaturated fats are classified as either monounsaturated fats or polyunsaturated fats. Fats that have all the hydrogen the carbon atoms can hold are called saturated fats. Saturated fats are usually solid at room temperature (butter, ghee, lard, margarine).

Too much saturated fat in your diet can lead to heart disease. Nutritionists recommend that 20-35% of your calories come from fat, primarily unsaturated fat.

[Solved] Which nutrient provides the maximum energy on breakdown?

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RRB JE Previous Paper 11 (Held On: 25 May 2019 Shift 3)

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1. Carbohydrates
2. Fats
3. Fibres
4. Proteins

Option 2 : Fats

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Fat is the correct answer.

• Fats:
  • Fats are the slowest source of energy but the most energy-efficient form of food.
  • Fat molecules consist of primarily carbon and hydrogen atoms and some of them essential for diet.
  • Fats provide a source of concentrated energy as well as the fat-soluble vitamins A, D, E, and K.
  • It is needed for hormone metabolism, healthy skin and hair, tissue repair, protecting the internal organs and to prevent excessive loss of body heat.
• Carbohydrate:
  • A carbohydrate is an organic compound that consists only of carbon, hydrogen, and oxygen, usually with a hydrogen: Oxygen: atom ratio 2:1.
  • The body uses carbohydrates to make glucose which is the fuel that gives energy and helps keep everything going.
  • The body can use immediately or store it in the liver and muscles for when it is needed. Glucose is a carbohydrate which is the major fuel for the cells in the body.
• Proteins:
  • Proteins, building blocks of life, are compounds of carbon, oxygen, hydrogen and nitrogen.
  • Majority of proteins contain sulphur.
  • It is made up of numerous monomers, the amino acids, which are joined together by peptide bonds.
  • It is a major part of skin, muscles, organs, and glands and also found in all body fluids, except bile and urine.
• Fibres:
  • Fibre is the indigestible parts of plant foods, such as vegetables, fruits, grains, beans and legumes. It is a type of carbohydrate that helps keep our digestive systems healthy.

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Carbohydrates | Tervisliku toitumise informatsioon

Carbohydrates are the main source of energy in the body. Energy from dietary carbohydrates comes primarily from starches and sugars, and to a lesser extent from dietary fiber and sugar alcohols.

The main sources of carbohydrates are cereals and potatoes. Fruits, fruit juice, berries and milk also contain sugars (mono- and disaccharides). Sweets, sugary drinks, fruit syrups, sweetened confectionery, and flavored dairy products are major sources of added sugars. Added sugars are sugars added to foods during processing or preparation.

Carbohydrate and sugar are not the same thing. Sugar is a conventional term used primarily for sucrose (so-called table sugar) as well as other water-soluble, sweet-tasting simple carbohydrates (mono- and disaccharides such as glucose, fructose, lactose, maltose).

• Carbohydrates should cover 50-60% of the daily dietary energy requirement.
• Energy from added sugar should not exceed 10% of daily dietary energy.

A person with a daily energy requirement of 2000 kcal per day should consume: 0.5 x 2000 kcal / 4 kcal = 250 g to 0.6 x 2000 / 4 kcal = 300 g of carbohydrates. With a daily energy requirement of 2500 kcal, the recommended daily amount of carbohydrates is 313-375 g, with 3000 kcal – 375-450 g.

Our body, and especially the brain, needs a constant supply of glucose to ensure the efficiency and effectiveness of its work. With a prolonged lack of carbohydrates, the body begins to synthesize glucose from its own proteins, which significantly reduces its protective ability against environmental factors.

In terms of nutritional value, carbohydrates are divided into two large groups:

Carbohydrates perform many functions in the body:

• are the main source of energy in the body: 1 gram of carbohydrates = 4 kcal0014
• are part of cells and tissues,
• determine the blood type,
• are part of many hormones,
• perform a protective function in the composition of antibodies,
• play the role of a reserve substance in the body: glycogen accumulated in the liver and muscles is a temporary reserve glucose, which the body can easily use if necessary,
• Dietary fiber is essential for the proper functioning of the digestive system.

Main carbohydrates and their best sources:

Mono- and disaccharides*, i.e. simple carbohydrates, i.e. sugars
Glucose, or grape sugar	honey, fruits, berries, juices
Fructose or fruit sugar	fruit, berries, juices, honey
Lactose or milk sugar	milk and dairy products
Maltose or malt sugar	cereal products
Sucrose or table sugar	sugar cane, sugar beet, table sugar, sugar-containing products, fruits, berries
Oligosaccharides
Maltodextrin	is produced from starch and is used primarily as a dietary supplement. Also found in beer and bread
Raffinose	legumes
Polysaccharides
Starch	potatoes, grains Fresh products, rice, pasta
Dietary fibers (cellulose, pectin)	cereals, fruits

fiber is found only in plants, for example, cellulose and pectin are found mainly in whole grains foods, fruits and vegetables, and legumes.

Microorganisms living in the intestines are able to partially break down dietary fiber, which is food for the microbes of the digestive tract, which in turn are important for the defenses of the human body.

Dietary fiber:

• ​increases the volume of food porridge, thereby causing a feeling of satiety,
• accelerates the movement of food through the small intestine,
• helps prevent constipation and may prevent some forms of cancer, cardiovascular diseases and diabetes II types,
• facilitate the removal of cholesterol from the body,
• slow down the absorption of glucose, preventing too sharp an increase in blood sugar levels,
• help maintain normal body weight.

Dietary fibers are not absorbed in the body, but due to partial decomposition in the intestines under the influence of the microflora of the digestive tract, they form fatty acids with a short molecular chain and provide about 2 kcal/g of energy.

Dietary fiber can be divided into water-soluble and insoluble. Since they perform different functions, you should consume foods containing both types of dietary fiber daily:

• Oats, rye, fruits, berries, vegetables and legumes (peas, lentils, beans) are good sources of water-soluble dietary fiber.
• Whole grains (rye bread, whole wheat bread, sepik, cereals, whole grain cereal, whole grain rice) are good sources of water-insoluble dietary fiber.

An adult should receive 25 to 35 g of dietary fiber per day, depending on the daily energy requirement (approx. 13 g of dietary fiber per 1000 kcal).

The recommended daily amount of dietary fiber for a child older than one year is 8-13 g per 1000 kcal of energy intake. The recommended daily amount for a child can be roughly calculated using the formula “age + 7”. Excessive consumption of dietary fiber is not recommended, since there is a danger that any mineral substance necessary for the body will be bound in a sparingly soluble compound, and the body will not be able to absorb it.

Recommendations for increasing intake of foods rich in starch and dietary fiber:

• When choosing a main course, opt for whole grain pasta or rice and less sauce.
• For sausages with boiled potatoes, use more potatoes and fewer sausages.
• Add beans and peas to stews, vegetable casseroles or stews. This will increase the content of dietary fiber in the dish. By acting in this way, you can eat less meat, meals become more economical, and the amount of saturated fatty acids consumed is also reduced.
• Prefer whole grain rye and wheat bread.
• Choose whole-grain rice: it contains a lot of dietary fiber.
• Eat whole grain cereal for breakfast or mix it into your favorite cereal.
• Porridge is a great warming winter breakfast, whole grain oatmeal with fresh fruits, berries and yogurt is a refreshing summer breakfast.
• Eat 3-5 slices of whole grain rye bread a day.
• Eat at least 500 g of fruits and vegetables per day.

Sugar

Most people tend to consume too much sugar because they eat a lot of sweets, cakes, pastries and other sugar-rich foods, drink soft drinks and juice drinks. The sugars found in unprocessed foods like fruit and milk are not to be feared. First of all, you should reduce the consumption of food containing added sugar.

Sugar is added to many foods, but most of all it contains:

• soft drinks and juice drinks: for example, 500 ml of lemonade can contain up to 50 g, i.e. 10-15 teaspoons of sugar,
• sweets, sweets, biscuits,
• jams,

The main disadvantages of many sugar-rich foods are, on the one hand, their relatively high energy content, and, on the other hand, their generally rather low content of vitamins and minerals. In addition, many sugar-laden foods are also high in fat, such as chocolate, cookies, muffins, cakes, and ice cream.

Sugar-rich foods and drinks can damage your teeth if you do not pay enough attention to oral hygiene. Teeth should be thoroughly brushed at least 2 times a day, and cleaned between meals, for example, with chewing gum. While the sugars found in fruit aren’t that bad for teeth, they’re already broken down in juices and are just as bad for teeth as any other sugar-rich food, especially if eaten frequently. Drinking a glass of fruit juice a day is still recommended (and preferably with food), as it enriches our table with vitamins, minerals and phytochemicals.

Eating less sugar is a solution!

What is the main source of energy in the human body?

April 19, 2018

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Carbohydrates are the main source of energy

It has long been known that nothing in the world arises from the void and does not disappear into nowhere. This fully applies to our energy reserves. Let’s try to figure out what is the main source of energy in the human body and what ways to replenish it can be called the most effective.

In contrast to the plant world, which successfully uses the method of photosynthesis to convert solar energy, a person is deprived of such an opportunity. Therefore, we need to use food of plant and animal origin. At the same time, do not forget to take into account that all products differ in their energy value (not to mention the ability to work both for good and for harm).

Discussion of the calorie content of certain dishes has long been on everyone’s lips. But what is it like in ordinary language? In fact, everything is quite easy. A calorie is a unit of energy that has a simple calculation formula: the amount of heat that raises the temperature of 1 gram of water by 1 degree. Accordingly, caloric content (it is also energy value) is the amount of energy that our body is able to acquire with the full assimilation of what is eaten.

Proteins, fats and carbohydrates are a complex of essential nutrients. At the same time, the role of the key energy “supplier” is assigned to carbohydrates, the level of which differs in different products. In addition, they are usually divided into simple (fast) and complex (slow) – we will talk about the features of each type later. Lean meats and fish are high-protein foods, while oils (both vegetable and animal) are a source of fat, for example.

Various trace elements and vitamins are also integral components, however, they primarily serve the processes of energy metabolism.

There is simply no universal formula that allows you to establish the exact amount (or ratio) of BJU for each, since the individual characteristics of each of us, as well as factors such as height, weight, metabolic rate, daily activity, lifestyle, bad habits, the regularity of playing sports – all this directly affects what the diet should be. Some general dependencies, of course, exist – for example, for people who are actively involved in sports training, the daily consumption rate can be quite high. And people who set themselves the goal of losing weight often make a serious mistake, thinking that it is enough to reduce the amount of calories consumed. Most often, this does not lead to any results in cases where physical activity is minimal. Lack of physical education in combination with a sedentary lifestyle, even with a minimum calorie content of food consumed, can not only not affect the situation with excess weight for the better, but also contribute to its further gain.

Let’s take a closer look at the mechanics of converting food into energy. After entering the stomach, the process of digestion of food is started, which does not stop even with its further advancement into the intestines (which is why the entire system is called the gastrointestinal system). Its purpose is to break down food into elements, some of which enters the bloodstream. It is worth noting that not all the energy received is immediately used by us. Some part plays the role of a reserve, being converted, including into fat. The less we move, the fewer calories we burn, the more intensively the fat layer increases.

At the beginning of the article, we mentioned simple and complex carbohydrates. It is time to remember them and explain the difference. The essence of the former lies already in the designation – their digestion occurs as quickly as possible, without additional efforts, moreover, the same applies to their assimilation. This is where their main negative property manifests itself – they increase appetite, provoking overeating and, as a result, accelerated weight gain. All types of sugar are simple varieties, so it is so easy to get fat from sweet and flour products, and you really want to eat “one more” cake.

Complex carbohydrates also go through the process of breaking down into glucose, however, it takes much longer. Thanks to them, we feel a feeling of fullness, at the same time some of them – starch and glycogen – supply us with energy. During meals, the level of glucose in the blood rises and it is in the form of glycogen that its excess amount is absorbed in the muscles and liver “in reserve”.