Pennsylvania State University

NUTR 251

Energy Balance and Body Composition

1)Define energy balance. What would be the result of positive energy balance? Negative energy balance? What does the body use for energy during a state of negative energy balance?

2. If Matt drank 2 beers (equal to 240 kcals) every day in addition to the kcals necessary to maintain body weight, how much weight would he gain in two weeks? Hint: How many Calories (kcals) are equivalent to one pound of adipose tissue (fat tissue)?
3. What does a bomb calorimeter measure?
4. The heat generated in a bomb calorimeter for protein is 5.6 kcal/g, yet

on a food label it tells me that protein is 4 kcal/gram. Why are these values different?

5. List the physiological fuel values for carbohydrate, protein, fat, and alcohol?

6. You just ate 2 slices of a medium pizza for lunch. Here is the nutrient analysis: 21 g of protein, 75 g of carbohydrates, 18 g of fat, and 4 g of fiber. How many kcals is in this meal? Calculate the percent kcals coming from fat.
7. Briefly, what is the difference between hunger, satiation, satiety, and appetite? Does the phrase “feeling fuller for longer” refer to satiety or satiation?
8. Comment on the effects of nutrient composition of a meal on satiation

and satiety. Define low energy density. Explain the difference between dietary fat having a low satiation in the stomach, versus fat producing satiety signals when in the small intestine (hint: think about CCK)

9. There are many chemicals and hormones that affect the brain and

levels of hunger and satiety. Describe the action of neuropeptide Y and cholecystokinin (CCK).

10. You expend energy (ie. Body uses food for fuel) in three categories. List

these categories and define them. For the average semi-sedentary American, what category is responsible for the most calorie expenditure? What percentage does BMR account for?

11. What factors or characteristics can raise basal metabolic rate (BMR) and what factors can lower basal metabolic rate?
12. What variables are accounted for in the DRI equation for calculating Total Energy Expenditure (this is called Estimated Energy Requirement in the text)?
13. Sarah’s BMI is 21.2 and Sonia’s BMI is 28.9. Would they be considered underweight, healthy weight, overweight or obese? List these cutoffs.
14. What are two other criteria (besides BMI) which should be used to determine healthy body status in an individual? Why is BMI not a perfect indicator of health risks? Some people need more body fat; explain.
15. Is your body an apple or a pear? So what, why is this important? What

are the cut-offs in terms of adult waist circumferences and risk for increased chronic diseases?