Intro to Nutrition CH.14 (PT.1)

What is energy balance?

The relationship between energy consumed and energy expended by the body.

What happens when there is an energy imbalance?

It can result in weight gain or weight loss.

What is positive energy balance?

When energy intake is greater than energy expended.

What can positive energy balance result in?

Weight gain from increased muscle mass, adipose tissue, or both.

During what periods of life is positive energy balance important?

Pregnancy, childhood, and adolescence.

What is negative energy balance?

When energy expended is greater than energy intake.

What can cause negative energy balance?

Reduced food intake, increased energy expenditure, or both.

What does negative energy balance result in?

Weight loss.

What can the body lose during negative energy balance?

Fat, muscle, glycogen, and water.

What provides the body with energy?

Foods and beverages.

What unit is used to measure energy in food?

Kilocalories (kcal).

What is a bomb calorimeter?

A device that measures the energy content of foods and beverages.

Why must bomb calorimeter results be adjusted?

To account for physiological fuel values.

What are physiological fuel values?

The actual kilocalories the body can obtain from nutrients.

What tools can be used to determine kilocalories in foods?

Nutrition analysis software and food composition tables.

How many kilocalories are in 1 gram of carbohydrates?

4 kilocalories.

How many kilocalories are in 1 gram of protein?

4 kilocalories.

How many kilocalories are in 1 gram of fat?

9 kilocalories.

What causes the body to expend energy?

Body processes and physical activity.

What four factors affect daily energy expenditure?

Basal metabolism, thermic effect of food, thermic effect of exercise, and adaptive thermogenesis.

What is basal metabolism?

Energy used to maintain basic body functions at rest.

What is the thermic effect of food (TEF)?

Energy used to digest, absorb, and metabolize food.

What is the thermic effect of exercise?

Energy expended during physical activity.

What is adaptive thermogenesis?

Changes in energy expenditure as the body responds to its environment and other conditions.

Why is knowing energy expenditure important?

It helps explain energy balance and changes in body energy stores.

What is Total Daily Energy Expenditure (TDEE)?

The total kilocalories the body uses to meet daily energy requirements.

What are the main components of TDEE?

Basal metabolism, thermic effect of food, physical activity, and adaptive thermogenesis.

Is TDEE the same for everyone?

No, daily energy needs vary from person to person.

What is basal metabolic rate (BMR)?

The amount of energy used to meet the body's basic physiological needs.

What are the factors that influence BMR?

Lean body mass, age, gender, body size, genes, ethnicity, stress, thyroid hormones, nutritional state, temperature, caffeine, and nicotine.

How does lean body mass affect BMR?

More lean body mass generally increases BMR.

How does age affect BMR?

BMR generally decreases with age.

How does body size affect BMR?

Larger bodies generally require more energy.

How do genes affect BMR?

Genetics can influence how much energy the body uses at rest.

How does emotional and physical stress affect BMR?

Stress can increase energy expenditure.

How do thyroid hormones affect BMR?

Thyroid hormones regulate metabolic rate.

How does nutritional state affect BMR?

Nutritional state can change how much energy the body uses at rest.

How does environmental temperature affect BMR?

Extreme temperatures can increase energy needs.

How do caffeine and nicotine affect BMR?

They can temporarily increase metabolic rate.

Why is resting metabolic rate (RMR) often used instead of BMR?

Because BMR is difficult to measure.

What is resting metabolic rate (RMR)?

The amount of energy the body uses while resting.

What is the thermic effect of exercise (TEE)?

Energy expended through increased muscle activity during exercise.

What three factors affect energy expenditure during exercise?

Type of activity, duration, and body weight.

How does the type of physical activity affect TEE?

Different activities require different amounts of energy.

How does exercise duration affect TEE?

Longer activity generally uses more energy.

How does body weight affect TEE?

Body weight influences the energy required for physical activity.

What is NEAT?

Energy used during daily activities that are not considered exercise.

What are examples of NEAT?

Walking around the house, standing, cleaning, and other daily movements.

What is the thermic effect of food (TEF)?

Energy used to digest, absorb, and process nutrients from food.

What percentage of kilocalories consumed is typically used for TEF?

About 10 percent.

Which macronutrient has the highest thermic effect of food?

Protein.

Which macronutrient has the lowest thermic effect of food?

Fat.

What is the order of macronutrients from highest to lowest TEF?

Protein → Carbohydrates → Fat.

How do high-protein meals compare with high-carbohydrate meals in TEF?

High-protein meals have a greater TEF.

How do high-carbohydrate meals compare with high-fat meals in TEF?

High-carbohydrate meals have a greater TEF.

What factors influence TEF?

Nutrient type, meal composition, alcohol intake, age, and athletic training status.

Why does the body use energy after eating?

To digest, absorb, and metabolize nutrients.

What is adaptive thermogenesis?

The body's regulation of heat production in response to environmental changes.

What factors influence adaptive thermogenesis?

Stress, temperature, and diet.

How does adaptive thermogenesis affect metabolism?

It causes changes in the body's metabolic rate.

Why do researchers think adaptive thermogenesis is important?

It may explain why people with similar diets and exercise patterns have different body compositions.

What are the two methods used to measure energy expenditure?

Direct calorimetry and indirect calorimetry.

What is direct calorimetry?

Measuring energy expenditure by assessing body heat loss.

What equipment is used for direct calorimetry?

A metabolic chamber.

What is indirect calorimetry?

Estimating energy expenditure by measuring oxygen consumed and carbon dioxide produced.

What equipment is used for indirect calorimetry?

A metabolic cart.

What does direct calorimetry measure?

Body heat loss.

What does indirect calorimetry measure?

Oxygen consumption and carbon dioxide production.

What factors are used to estimate total energy expenditure?

Age, gender, height, weight, and physical activity level.

What is Estimated Energy Requirement (EER)?

An estimate of the energy needed to meet daily energy requirements.

What equation is used to estimate resting metabolic rate (RMR)?

The Harris–Benedict equation.

What factors are used in the Harris–Benedict equation?

Gender, height, weight, and age.

What is needed with the Harris–Benedict equation to estimate TDEE?

An activity factor.

What is body composition?

The ratio of fat tissue to lean body mass.

What makes up lean body mass?

Muscle, bone, and organs.

How is body composition usually expressed?

As percent body fat.

Why is body composition assessed?

To help evaluate health risks associated with excess body fat.

What are the two types of fat that make up total body fat?

Essential fat and stored fat.

What is essential fat?

Fat needed for the body to function properly.

What percentage of essential fat is listed for women?

12 percent.

What percentage of essential fat is listed for men?

3 percent.

What is stored fat?

Fat stored in adipose tissue.

What is adipose tissue?

Body tissue that stores fat.

What is subcutaneous fat?

Fat located underneath the skin.

What is visceral fat?

Fat stored around internal organs in the abdominal area.

What are two functions of stored body fat?

Insulating the body from cold temperatures and protecting internal organs.

How does stored fat help regulate body temperature?

It insulates the body against cold temperatures.

How does stored fat protect organs?

It cushions and protects internal organs.

What happens to adipose tissue during negative energy balance?

Stored fat is released for energy, and adipocytes shrink.

What are adipocytes?

Fat cells that store energy.

What happens to adipocytes during positive energy balance?

They expand as fat accumulates.

What happens to fat stores during negative energy balance?

They are used to help provide energy.

What happens to fat stores during positive energy balance?

They can increase as excess energy is stored.

What is brown adipose tissue?

A specialized type of fat tissue that produces heat.

What makes brown adipose tissue different from other fat tissue?

It contains more mitochondria and has a rich blood supply.

What is the main function of brown adipose tissue?

To generate heat.

Why does brown adipose tissue contain many mitochondria?

To help produce heat through energy metabolism.

What is another name for heat production in the body?

Thermogenesis.

What is central obesity?

excess visceral fat stored in the abdomen.

What is another name for central obesity?

Android obesity.