Energy Balance and Weight Management

Energy Intake Energy Output Energy Equilibrium Positive Energy Balance Negative Energy Balance

Energy In Regulation of intake Hunger Prompts eating; physiological desire Satiation Signals to stop eating Satiety Lack of hunger Appetite Psychological desire

Stimulates for hunger, satiation and appetite Diet Composition Gastrointestinal Sensations Temperature Neurological and Hormonal Factors Environmental and Social Factors

Your body uses fuel (expends energy) for 3 primary purposes: 1. Maintain basic physiological functions: breathing, blood circulation, etc. 2. To power physical activity 3. To process food you eat

Energy Out: Fuel Uses Major components of energy expenditure Resting energy expenditure (REE) Energy for basic body functions Affected by body size, composition, age, gender Physical activity Highly variable Affected by body size, fitness level, type of activity Thermic effect of food (TEF) Energy to digest, absorb, metabolize food

Factors that Increase RMR Decrease RMR Fever* Stress Total body weight Smoking * Caffeine High Lean Body Mass Rapid growth Hot & cold ambient temp Pregnancy, lactation Hyperthyroidism Large body surface area Aging Female Fasting/Starvation Sleep Hypothyroidism

Estimating Total Energy Expenditure Estimating REE from body weight, gender, and age Estimating Total energy expended from REE and physical activity Harris-Benedict equation w: (wt:kg) (ht:cm) (age:yrs) m: (wt:kg) = 5.0 (ht:cm) (age:yrs) RDA for energy

Estimating REE from body weight, sex and age: REE for female, age 18-30= (14.7 x weight (kg)) wt=130 lbs..=59 kg = (14.7 x 59) =1363 Harris-Benedict equation (kg) (cm) (yrs) (59) (167.64) (22) =1426 REE x activity level = total energy expenditure REE x (light activity level) = 1363 x = = kcals 1426 x = = kcals RDA (women age 19-50) = 2,200 kcals (wt. of 121 lbs.)

Body Composition: Understanding Fatness and Weight Assessing body weight Height-weight tables Men: 106 lbs + 6 lbs per inch Women: 100 lbs. + 5 lbs per inch Body mass index (BMI) Weight (kg)  height 2 (m)

When Energy Balance Goes Awry Definitions Overweight: BMI between Obesity: BMI > 30 Underweight: BMI < 18.5 Health risks of overweight and obesity Heart disease and stroke Hypertension --Gallbladder disease Diabetes ---Sleep apnea Cancer Osteoarthritis

Assessing Body Fatness Women = 20-25% Men = 12-20% Underwater (or hydrostatic) weighing BodPod Skinfold thickness Bioelectrical Impedance Analysis DEXA

Average Body Composition

Body fat distribution Android greater health risk high blood lipids, glucose intolerance, insulin resistance, and high blood pressure Gynoid Waist circumference assess abdominal fatness BMI , waist >40 inches in men and > 35 inches in women is sign of increased health risk

When Energy Balance Goes Awry Early theories of weight regulation Fat cell theory Obesity increases number and size of fat cells Set point theory Influences on weight gain and obesity Heredity and genetic factors Sociocultural influences Age and lifestyle factors Gender and ethnicity Socioeconomic factors Psychological factors

Weight Management Weight management is the adoption of healthful and sustainable eating and exercise behaviors indicated for reduced disease risk and improved feelings of energy and well-being

Weight Management Perception of weight Setting realistic goals Weight management lifestyle Diet and eating habits Reduce total calories Reduce fat calories Increase complex carbohydrates Improve eating habits Increase physical activity Stress management Self-acceptance

Weight Management Weight management approaches Self-help books and manuals Watch for signs of a fad diet Self-help groups Commercial programs Professional counselors Prescription drugs OTC drugs and dietary supplements Surgery

Underweight Definition BMI < 18.5 Causes and assessment Illness Eating disorders Metabolic factors Weight-gain strategies Small, frequent meals Fluids between meals High-calorie foods and beverages