Chapter 10 - Energy Balance, Weight Control, and Eating Disorders Flashcards
Energy Balance
State in which energy intake, in the form of food and beverages, matches energy expended, primarily through basal metabolism and physical activity
Equilibrium
In nutrition, a sate in which nutrient intake equals nutrient losses. Thus, the body maintains a stable condition, such as energy equilibrium.
Positive Energy Balance
State in which energy intake is greater than energy expended, generally resulting in weight gain
When is positive energy balance desired?
During pregnancy, infancy, childhood, adolescence, and after losses due to starvation, disease, or injury.
Negative Energy Balance
State in which energy intake is less than energy expended, resulting in weight loss
When is negative energy balance desired?
It’s desired in adults when their body fatness exceeds healthy levels.
Basal Metabolism
Minimum amount of energy the body uses to support itself when fasting, resting, and awake in a warm, quiet environment. Expressed as basal metabolic rate (BMR)
Basal metabolism accounts for how much of the body’s total energy expenditure?
60-70%
Resting Metabolism
Amount of energy the body uses when the person hasn’t eaten in four hours and is resting and awake in a warm, quiet environment. Expressed as resting metabolic rate (RMR)
How much higher is the RMR than the BMR?
typically 6% higher
What are the factors that increase basal metabolism? (9 things)
- greater muscle mass
- larger body surface area
- male gender
- body temperature
- higher than normal thyroid hormone secretions
- nervous system activity
- growth stages of the life cycle
- caffeine and tobacco use
- recent exercise
Of the factors that increase basal metabolism, which is the most important?
Greater muscle mass
What are the factors that decrease basal metabolism? (4 things)
- lower than normal thyroid hormone secretions
- restricted calorie intake
- less body surface area and muscle mass
- aging after age 30
Physical activity increases energy expenditure above basal energy needs by how much?
25-40%
Thermic Effect of Food (TEF)
Energy the body uses to digest, absorb, transport, store, and metabolize nutrients
TEF accounts for how much energy consumed each day?
5-10%
Thermogenesis
Heat production by humans. Produced when the body expends energy for involuntary physical activity triggered by cold conditions or overeating.
What type of tissue releases much of its energy from energy-yielding nutrients as heat and why?
Brown adipose tissue; it has an uncoupling protein that causes this
Direct Calorimetry
Method of determining a body’s energy use by measuring heat that is released from the body, usually using an insulated chamber
Indirect Calorimetry
Method to measure energy use by the body by measuring oxygen uptake. Formulas are used to convert this gas exchange value into energy use.
What is the most commonly used measurement of energy use?
Indirect Calorimetry
How do you determine the EER of a male older than 19?
EER = 662 - (9.53 x age) + physical activity estimate x ([15.91 x weight (kg)] + [593.6 x height (m)])
How do you determine the EER of a female older than 19?
EER = 354 - (6.91 x age) + physical activity estimate x ([9.36 x weight (kg)] + [726 x height (m)])
Satiety
State in which there is no longer a desire to eat; feeling of satisfaction
Sympathetic Nervous System
Part of the nervous system that regulates involuntary vital functions, including the heart muscle, smooth muscle, and adrenal glands
What is the process of satiety? (4 steps)
- Flavor of food
- Knowing a meal was just eaten
- Influence of stomach and intestinal expansion and activity
- Influence of nutrient use in the liver and related communication with the hypothalamus and other regions of the brain