chapter 8 energy balance and body composition
TRANSCRIPT
Energy Balance and Body Composition
Studying = 1 or 2 kcalories/minute
Energy Balance
Food Composition
• Direct calorimetry vs. indirect calorimetry
• Physiological fuel value
Food Intake • Hunger• Appetite• Satiation• Satiety• Overriding hunger and satiety
– Stress eating• Sustaining satiation and satiety
– satiating
Food Intake
• Sustaining satiation and satiety– lower-fat foods can be eaten in
larger portions for the same number of kcalories
Food Intake
Food Intake
• Hypothalamus– Neuropeptide Y
Thermogenesis
• Basal thermogenesis
• Exercise-induced thermogenesis
• Diet-induced thermogenesis
• Adaptive thermogenesis
Components of Energy Expenditure
Components of Energy Expenditure
• Basal metabolism• Basal metabolic rate (BMR)• Resting metabolic rate (RMR)• Physical activity
Components of Energy Expenditure
• Thermic effect of food (TEF)
• Diet-induced thermogenesis (DIT)
Estimating Energy Requirements
• Gender
• Growth
• Age
Estimating Energy Requirements
• Physical activity
• Body composition
• Body size
Body Weight, Body Composition,
and Health
• Body composition
• Body weight = fat + lean tissue (including water)
Defining Healthy Body Weight
• The criterion of fashion: BMI of Miss America
Defining Healthy Body Weight
• The criterion of health• Body mass index (BMI)
=weight (kg)/height (m)2
BMI Values Used to Assess Weight
Distribution of Body Weights in U.S. Adults
Body Fat and Its Distribution
Body Fat and Its Distribution
• Some people need less body fat
• Some people need more body fat
Body Fat and Its Distribution
• Fat distribution– Intra-abdominal fat– Central obesity
Body Fat and Its Distribution
• Waist circumference-according to some...if it’s anything over 35”, it’s too much!
Body Fat and Its Distribution
• Other measures of body composition– Fatfold measure– Hydrodensitometry– Bioelectrical impedance
Body Fat and Its Distribution
• Other measures of body composition– Air displacement
plethysmography– Dual energy X-ray
absorptiometry (DEXA)
Methods Used to Assess Methods Used to Assess Body FatBody Fat
Health Risks Associated With Body Weight and
Body Fat
• Health risks of underweight
• Health risks of overweight
BMI and Mortality
Health Risks Associated With Body Weight and Body Fat
• Cardiovascular disease• Diabetes• Cancer• Fat and fit versus sedentary and
slim
The Latest and Greatest Weight-Loss Diet - Again
• The claims and truths of diet fads• High-protein, low carbohydrate diets
– The diet’s appeal
The Latest and Greatest Weight-Loss Diet - Again
• High-protein, low carbohydrate diets– Don’t count kcalories– Satisfy hunger– Follow a plan– Limit choices
The Latest and Greatest Weight-Loss Diet - Again
• High-protein, low carbohydrate diets– Too much fat– Too much protein– Too little everything else– The body’s perspective
Questions or Thoughts
• If you have any questions or thoughts please feel free to post them in the Discussion Forum/Board or you can e-mail your instructor