Energy Balance and Weight Management: Finding Your Equilibrium

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1 Chapter 9 Energy Balance and Weight Management: Finding Your Equilibrium Key Terms 1. appetite: A psychological desire to eat that is related to the pleasant sensations often associated with food. 2. extreme obesity: Obesity characterized by body weight exceeding 100 percent of normal; a condition so severe it often requires surgery. 3. waist circumference: The waist measurement; as a marker of abdominal fat content, it can be used to indicate health risks. 4. energy balance: The balance in the body between amounts of energy consumed and expended. 5. leptin: A hormone produced by adipose cells that signals the amount of body fat content and influences food intake. 6. hypothalamus: A region of the brain involved in regulating hunger and satiety, respiration, body temperature, water balance, and other body functions. 7. basal energy expenditure (BEE): The basal metabolic rate (BMR) extrapolated to 24 hours. Often used interchangeably with REE. 8. gynoid obesity: Excess storage of fat located primarily in the buttocks and thighs. Also called gynecoid obesity. 9. hunger: The internal, physiological drive to find and consume food. Unlike appetite, this is often experienced as a negative sensation, often manifesting as an uneasy or painful

2 sensation. The recurrent and involuntary lack of access to food that may produce malnutrition over time. 10. body mass index (BMI): Body weight (in kilograms) divided by the square of height (in meters), expressed in units of kg/m energy intake: The caloric or energy content of food provided by the sources of dietary energy: carbohydrate (4 kcal/g), protein (4 kcal/g), fat (9 kcal/g), and alcohol (7 kcal/g). 12. basal metabolic rate (BMR): A clinical measure of resting energy expenditure performed upon awakening, 10 to 12 hours after eating, and 12 to 18 hours after significant physical activity. Often used interchangeably with RMR. 13. energy equilibrium: A balance of energy intake and output that results in little or no change in weight over time. 14. android obesity: Excess storage of fat located primarily in the abdominal area. 15. energy output: The use of calories or energy for basic body functions, physical activity, and processing of consumed foods. 16. negative self-talk: Mental or verbal statements made to one s self that reinforce negative or destructive self-perceptions. 17. resting energy expenditure (REE): The minimum energy needed to maintain basic physiological functions (e.g., heartbeat, muscle function, respiration). The resting metabolic rate (RMR) extrapolated to 24 hours. Often used interchangeably with BEE. 18. body fat distribution: The pattern of fat distribution on the body. 19. lean body mass: The portion of the body exclusive of stored fat, including muscle, bone, connective tissue, organs, and water.

3 20. total energy expenditure (TEE): The total of the resting energy expenditure (REE), energy used in physical activity, and energy used in processing food (TEF); usually expressed in kilocalories per day. 21. satiation: Feeling of satisfaction and fullness that terminates a meal. 22. metabolic fitness: The absence of all metabolic and biochemical risk factors associated with obesity. 23. satiety: The effect of a food or meal that delays subsequent intake. Feeling of satisfaction and fullness following eating that quells the desire for food. Fill-in-the-Blank 1. The ABC model of behavior is a behavioral model that includes the external and internal events that precede and follow the behavior. This involves antecedents and the events that precede the behavior, followed by consequences that positively or negatively reinforce the behavior. 2. Constructive mental or verbal statements made to one s self to change a belief or behavior are called positive self-talk. 3. A BodPod is a device used to measure the density of the body based on the volume of air displaced as a person sits in a sealed chamber of known volume. 4. A person is underweight if he or she has a BMI less than 18.5 kg/m The output of energy associated with fidgeting, maintenance of posture, and other minimal physical exertions is nonexercise activity thermogenesis (NEAT). 6. A person is overweight if his or her BMI is at or above 25 kg/m 2 and less than 30 kg/m 2.

4 7. Neuropeptide Y (NPY) is a neurotransmitter widely distributed throughout the brain and peripheral nervous tissue. Its activity has been linked to eating behavior, depression, anxiety, and cardiovascular function. 8. Negative energy balance occurs when energy intake is lower than energy expenditure, resulting in a depletion of body energy stores and weight loss. 9. Resting metabolic rate (RMR) is a clinical measure of resting energy expenditure performed three to four hours after eating or performing significant physical activity. 10. Bioelectrical impedance analysis (BIA) is a technique used to estimate amounts of total body water, lean tissue mass, and total body fat. It uses the resistance of tissue to the flow of an alternating electric current. 11. Obesity occurs when a person has a BMI at or above 30 kg/m Ghrelin is a hormone produced by the stomach that stimulates feeding by increasing release of neuropeptide Y. 13. Diets supplying 400 to 800 kilocalories per day that include adequate high-quality protein, little or no fat, and little carbohydrate are called very-low-calorie diets (VLCD). 14. Determining body density by measuring the volume of water displaced when the body is fully submerged in a specialized water tank is called hydrostatic (underwater) weighing. 15. The thermic effect of food (TEF) is the energy used to digest, absorb, and metabolize energy-yielding foodstuffs. It constitutes about 10 percent of total energy expenditure but is influenced by various factors. 16. The adoption of healthful and sustainable eating and exercise behaviors that reduce disease risk and improve well-being is weight management.

5 17. Positive energy balance occurs when energy intake exceeds energy expenditure, resulting in an increase in body energy stores and weight gain. 18. Body composition is the chemical or anatomical composition of the body. It is commonly defined as the proportions of fat, muscle, bone, and other tissues in the body. Fill-in-the-Blank Summaries Body Composition The National Institutes of Health released guidelines in 1998 that define obesity in adults as a BMI of greater than 30 kg/m 2. The BMI has a limited ability to distinguish between muscle weight and excess fat weight. Densitometry is the measure of body density. In hydrostatic (underwater) weighing, body density is calculated using the above-water weight, the submerged weight, and the quantity of water displaced during submersion. Done correctly, body composition estimates from skinfold thickness measurements correlate well with hydrostatic (underwater) weighing. Skinfold measurements are especially useful in tracking changes to subcutaneous fat distribution over time. Body fat distribution can be a risk factor for heart disease and diabetes. Gynoid obesity is more common in women and refers to excess fat being distributed around the hips and thighs. Android obesity is more common in men and has excess fat distributed around the abdomen. Short Answer 1. Explain some of the negative factors caused by living in a built environment.

6 Answer should include the following information: Living in a built environment may involve living in a neighborhood with low walkability or access to a supermarket. This can lead to a higher BMI in those individuals who cannot be active in their own neighborhoods, or who only have easy access to fast food restaurants and convenience stores. 2. What are some of the risks associated with being overweight? Identify three (3) risks. Answer may include any of the following: Heart disease and stroke; diabetes; cancer; sleep apnea; osteoarthritis; gout; gallbladder disease. 3. In what forms does your body store excess Kcalories when you are in a state of positive energy balance? Under what circumstances is a positive energy balance not only healthy, but also necessary? When you take in more energy than you need, you have a positive energy balance and you store the surplus as fat and as glycogen. Pregnancy, growing children, and anyone who is in need of weight gain require a positive energy balance. 4. How does your body obtain fuel for its energy needs if you are in negative energy balance? When you take in less energy than you need, you have a negative energy balance. To obtain fuel, your body uses stores of glycogen and fat (and breaks down body protein, too, if the deficit is extreme). 5. Calculate the amount of total Kcalories provided in a food that contains: 22 grams of carbohydrate, 2 grams of protein, and 6 grams of fat. 22 grams carbohydrate 4 Kcalories per grams = 88 Kcalories from carbohydrate 2 grams of protein 4 Kcalories per gram = 8 Kcalories from protein

7 6 grams of fat 9 Kcalories per gram = 54 Kcalories from fat = 150 total Kcalories 6. A child refusing to go to bed without a bedtime snack is likely responding to a social circumstance or environmental condition. We classify this type of eating a result of what? External factors 7. The thermic effect of a 900-Kcalorie meal is about how many Kcalories? 90 Kcalories (or 10%) 8. To be in the best possible recommended health BMI range, would a person with a BMI of 21 want to gain, lose, or maintain their current weight? Maintain 9. Identify specific consequences associated with excess abdominal fat, or android obesity. Excess abdominal fat appears to raise blood lipid levels, which in turn interferes with insulin function. Consequently, android obesity has been linked to high blood lipids, glucose intolerance and insulin resistance, and high blood pressure; it increases the risk of heart disease and diabetes mellitus. 10. Discuss reasonable dietary strategies for achieving and maintaining a healthy body weight. The way to gain weight is to create a positive energy balance. Here are some healthy strategies: Have small, frequent meals consisting of nutrient-dense and energy-dense foods and beverages.

8 Drink fluids at the end of the meal or, better yet, between meals to avoid filling the stomach with liquids of low nutrient density. Try high-calorie weight-gain beverages and foods. Use timers or other cues to prompt eating. Take a balanced vitamin/mineral supplement to ensure that poor appetite isn t a result of nutritional deficiency. 11. A nutritionally sound and successful weight-loss diet approach would be to restrict daily energy intake by about how many Kcalories per day? You are more likely to control your weight successfully by cutting 200 to 300 kilocalories per day. Journal Activity 1. Perform an Internet search for a BMI calculator to determine your own body mass index. Based on your results, are there any changes you would make in terms of diet or activity level? Answers will vary based on individual. Answer should contain reasonable analysis of the individual s results. 2. Being moderately active can involve many different activities. What kinds of activities are considerate moderate? Answers may include any of the following: Washing and waxing a car for 45 to 60 minutes Washing windows or floors for 45 to 60 minutes Playing volleyball for 45 minutes

9 Playing touch football for 30 to 45 minutes Gardening for 30 to 45 minutes Wheeling oneself in a wheelchair for 30 to 40 minutes Walking 1.5 miles in 35 minutes Basketball (shooting baskets) for 30 minutes Bicycling 3 miles in 30 minutes Fast social dancing for 30 minutes Pushing a stroller 1.5 miles in 30 minutes Raking leaves for 30 minutes Walking 2 miles in 30 minutes Water aerobics for 30 minutes Swimming laps for 20 minutes Wheelchair basketball for 20 minutes Basketball (playing a game) for 15 to 20 minutes Bicycling 4 miles in 15 minutes Running 1.5 miles in 15 minutes Shoveling snow for 15 minutes Climbing stairs for 15 minutes