1. Energy Balance, Weight Control and Eating Disorders Part 1 of 2
Chapter 10

2. Learning Outcomes
Describe the many factors that have resulted in an increase in obesity in the US
What is energy balance and what are the components of energy balance?
Know the methods used to measure energy expenditure by the body.
Explain internal and external regulation of hunger, appetite and satiety.
Describe the methods available to measure body composition. What tools are available to determine whether body weight and body composition are healthy?
Discuss the impact of genetics and environment on body weight and composition.

3. Obesity Trends* Among U.S. Adults BRFSS, 1990, 2000, 2010
(*BMI 30, or about 30 lbs. overweight for 5’4” person)
1990
2000
2010

5. The prevalence of childhood obesity is also increasing
Growth in Childhood Obesity Over Three Decades
Age 6 to 11: 4%→ 13%
Age 12 to 19: 5%→14%
If obese at age 6 → 50% chance of lifelong obesity
If obese at age 13 → 75% chance of lifelong obesity
Blacks
Mexican Americans
50% more likely to be obese than whites
From NHANES

6. How did we get from a prevalence of 45% to 65%?

7. Energy Balance
Energy
intake
Energy
expenditure

8. Energy Balance Energy equilibrium Positive energy balance
Energy intake equals energy expenditure
Positive energy balance
Energy intake greater than energy expenditure
Negative energy balance
Energy intake less than energy expenditure

9. Factors Affecting Energy Balance and Weight
Role of environment
Role of developmental behaviors
Role of genetics
Identical twins
Set point theory
Genetic and environment synergy
Diseases and disorders

10. Obesity: A Multifactorial Disorder
Genetics
Development
Behaviors/likes, etc
‘hard wired in’
Environment

11. Energy Intake Energy intake Energy intake
Estimated via nutrient databases
Calories based on bomb calorimeter
Fat 9 kcal/gm
Carbohydrates 4 kcal/gm
Protein 4 kcal/gm
Alcohol 7 kcal/gm
Energy
intake 11

12. Decrease your energy intake to lose weight
Daily calories to maintain a weight of 300 pounds kcal/day
To lose 1-2 pounds/week, you need to deficit 3500 kcal/pound
For 1 lb: 3500 kcal/7 days = kcal/day
For 2 lbs: kcal/7 days kcal/day
Daily calories to lose 1 pound/week kcal/day
Daily calories to lose 2 pounds/week kcal/day

13. Why is reducing kcal so hard?
Out of Control Environment
Stress and busy schedules
Skipped meals
Calorie-dense foods
Large portions
Increased variety

14. Contributions to Obesity: Learned Behaviors
“Clean your Plate” Club
Food as a coping mechanism
Food for celebration
Food is love
Food as a reward
Food as comfort
Learned
Behaviors

15. CHICKEN CAESAR SALAD 20 Years Ago Today 3 ½ cups 390 calories
Calorie Difference: 400 calories

16. *Based on 160-pound person
If you walk the dog for 1 hour and 20 minutes, you will burn approximately 400 calories.*
*Based on 160-pound person

17. It is easy to avoid “expending energy”
expenditure 17

18. Energy Expenditure Basal metabolic rate (BMR)
Minimum amount of energy in a fasting state
Factors that increase basal metabolism
Factors that decrease basal metabolism
Other factors that go into TOTAL energy expenditure:
Physical activity
Thermic effect of food
Adaptive thermogenesis

19. Measuring Energy Expenditure
Direct calorimetry
Measures body heat
Indirect calorimetry
Collecting expired air
Stable isotopes
Estimated energy requirements (EERs)
Harris-Benedict equation

20. Equations used to estimate energy needs
Harris Benedict
Women: = ( 4.35 x weight in pounds ) + ( 4.7 x height in inches ) - ( 4.7 x age in years ) Men: = 66 + ( 6.23 x weight in pounds ) + ( 12.7 x height in inches ) - ( 6.8 x age in year )
EER:
Similar but has physical activity built in to the equation
Also, has separate equations for adult men and women, toddlers, boys and girls aged 3-18, and obese girls and boys aged 3-18

22. Increase your energy expenditure to lose weight
To lose 1-2 pounds/week via exercise, you need to burn kcal in a week
You burn about 100 kcal/mile
Number of miles extra to lose 1 lb/wk miles or 5 miles/day
Number of miles extra to lose 2 lb/wk 70 miles or 10 miles/day 22

23. What controls energy balance?
intake
Energy
expenditure 23

24. Eating Behavior Regulation
Hunger
Physiological drive for food
Appetite
Psychological drive for food
Satiety
Fulfilling either drive
Hypothalamus regulates food intake: Gherlin, Leptin, Endorphins

27. Genes influence a person’s appetite, metabolism, and fat storage

28. Genes influence a person’s appetite, metabolism, and fat storage
100%
90%
50% 0%
Rare (Prader Willi, No Leptin production)
Leptin: Hormone made in fat tissue that decreases appetite and increases energy expenditure
Lipoprotein lipase: enzyme that promotes fat storage
More enzyme = more storage
Ghrelin: Protein secreted by stomach that stimulates appetite and promotes energy storage
Eat anything and not gain weight

29. Genetics dictate your “set point”
Forced dietary manipulation
Ad libitum fed

30. Gene-Environment Interactions in Obesity
Then:
Now: 30
Body Mass Index

31. Estimating Body Weight and Composition
Weight-for-height tables
Body Mass Index (BMI)

33. Weight and Health: Calculating BMI
BMI = weight in pounds x
(height, inches)2 Or
weight in kg
(height, meters)2

34. Assessing Body Fat Distribution
Upper body (Android)
Increased health risks
Men waist greater than 40 inches
Women waist greater than 35 inches
Lower body (Gynecoid)
Lower health risks

36. Risk of Associated Disease* According to BMI and Waist Size
Classification
Waist ≤ 40in (M) or 35in (W)
Waist > 40in (M) or 35in (W)
<18.5
Underweight --
Normal
May increase risk
Overweight
Increased
High
Obese (Class I)
Very High
Obese (Class II)
≥40
Obese (Class III)
Extremely High
*Type 2DM, HTN, and CVD

37. Measuring Body Fat Content
Underwater weighing
Air displacement
BodPod®
Skinfold thickness
Bioelectrical impedance
Dual energy X-ray absorptionmetry (DEXA)