© 2007 Thomson - Wadsworth Energy Balance & Healthy Eating

© 2007 Thomson - Wadsworth Energy Balance

© 2007 Thomson - Wadsworth Components of Energy Expenditure

© 2007 Thomson - Wadsworth Basal Metabolism Energy expended to sustain basic life functions Respiration, heart beat, nerve function, muscle tone Basal metabolic rate (BMR) Amount of energy expended per hour Accounts for 50-65% TEE BMR measured in morning, fasting state, & temperature-controlled room

© 2007 Thomson - Wadsworth Factors Influencing BMR Age Sex Growth Body shape Body composition Temperature Stress Fever Thyroid function Nutritional status

© 2007 Thomson - Wadsworth Physical Activity Accounts for 25-50% of TEE Factors affecting amount of energy needed: Time & intensity of activity Body size Fitness

© 2007 Thomson - Wadsworth Thermic Effect of Food Accounts for 5-10% of TEE Energy expended to digest, absorb, transport, metabolize, & store nutrients following a meal Influenced by: Amount & composition of food

© 2007 Thomson - Wadsworth Assessing Total Energy Expenditure (TEE) Direct calorimetry Indirect calorimetry Use of stable isotopes: Doubly labeled water Mathematical formulas DRIs Estimated Energy Requirements

© 2007 Thomson - Wadsworth Estimating Energy Requirements Males (19 years and older) EER = (9.53 x age) + PA x [(15.91 x wt) + (539.6 x ht)] Females (19 years and older) EER = 662 – (6.91 x age) + PA x [(9.36 x wt) + (726 x ht)] *Age in years, weight in kilograms, height in meters

© 2007 Thomson - Wadsworth Estimating Physical Activity Factor Description Physical Activity Equivalents Men: PA Factor Women: PA Factor Sedentary Only activities required for normal independent living 1.0 Activities equivalent to walking at a pace of 2-4 mph for the following distances: Low Active1.5 to 3.0 miles/day Active3 to 10 miles/day Very Active10 or more miles/day

© 2007 Thomson - Wadsworth EER Example Ex: 20 y.o. female, 5’4”, 123#, walks to class 5’4”  64 ÷ = 1.63 m 123#  123/2.2 = 55.9 kg EER = 662 – 6.91(20) [(9.36)(55.9) + (726)(1.63)] = 662 – [ ] = /- 10% = 2192 – 2679 kcal/day

© 2007 Thomson - Wadsworth Regulation of Energy Balance Brain uses information to coordinate adjustments in energy intake and expenditure to maintain energy balance on short- & long-term basis.

© 2007 Thomson - Wadsworth Short-Term Regulation of Food Intake

© 2007 Thomson - Wadsworth Hunger & Satiety Hunger Basic physiological need for food Satiety Physiological response to having eaten enough Influences Neuropeptides GI neural & hormonal signals Pancreas Adipose tissue

© 2007 Thomson - Wadsworth Appetite Desire for food Stimuli may override hunger & satiety Psychological vs physiological Influences Appearance, taste, aroma, emotional states General vs specific

© 2007 Thomson - Wadsworth Long-Term Regulation of Weight: Set Point Theory Thermostat analogy Energy-wasting proteins convert energy to heat When weight varies from “set point” Food intake changes Energy expenditure changes

© 2007 Thomson - Wadsworth Assessing Body Weight Body Mass Index (BMI) = [wt (kg)] / [ht (m) 2 ] Healthy = 18.5 – 24.9 kg/m 2 Overweight = kg/m 2 Obese ≥ 30 kg/m 2

© 2007 Thomson - Wadsworth BMI & Weight-Related Morbidity & Mortality

© 2007 Thomson - Wadsworth Other Body Measurements Body Composition Adipose vs Muscle, water, & bone Determinants: Genetics, sex, hormones, physical activity, diet “Normal” body fat levels Males = 12-20% Females = 20-30% Waist Circumference Men ≤ 40 inches Women ≤ 35 inches

© 2007 Thomson - Wadsworth Waist-to-Hip Ratio Indicator of body fat distribution

© 2007 Thomson - Wadsworth Problems with using anthropometric measurements to assess health BMI/Weight does not account for body composition, frame size, age, or ethnicity reported correlations between categories and health risk skewed Research most looks just at weight, not lifestyle factors Fitness is more important than fatness!

© 2007 Thomson - Wadsworth What is a healthy weight for you? Consider genetics Consider your own history How has your weight changed? How has your life changed? Consider your eating and exercise habits

© 2007 Thomson - Wadsworth Weight Management at UVa

© 2007 Thomson - Wadsworth BMI Data

© 2007 Thomson - Wadsworth Students’ Perceptions of their Weight

© 2007 Thomson - Wadsworth Students’ Intentions About Weight

© 2007 Thomson - Wadsworth

“Everyone is dieting…” 91% of women recently surveyed on a college campus had attempted to control their weight through dieting, 22% dieted “often” or “always” (Kurth et al., 1995)

© 2007 Thomson - Wadsworth “…even though dieting doesn’t work…” Evidence is inadequate to recommend commercial or self-help programs [for weight loss] (Tsai & Wadden, 2005) Programs restricting dietary fat and/or focusing on behavior modification are generally no more effective than traditional dieting techniques (Miller, 2006) 95% of all dieters will regain their lost weight in 1-5 years (Grodstein, et al., 1996)

© 2007 Thomson - Wadsworth “…and is, in fact, harmful.” Dieting problems include: Increased risk of heart disease Slowed metabolism Nutrient deficiencies Loss of muscular strength and endurance Interference with concentration and reaction time Increased stress, low self-esteem, and feelings of depression (NEDA 2006) 35% of “normal dieters” progress to pathological dieting. Of those, 20-25% progress to partial or full-syndrome eating disorders. (Shisslak & Crago, 1995)

© 2007 Thomson - Wadsworth Health At Every Size 1.Health enhancement 2.Size- and self-acceptance 3.Pleasure of eating well 4.Joy of movement 5.End to weight bias

© 2007 Thomson - Wadsworth Health At Every Size Pleasure of eating well Eating based on internal cues of hunger and satiety, appetite, and individual needs, rather than on external food plans or diets.

© 2007 Thomson - Wadsworth Intuitive Eating Unconditional permission to eat when hungry and what food is desired Eating for physical rather than emotional reasons Reliance on internal hunger and satiety cues to determine when and how much to eat

© 2007 Thomson - Wadsworth Does it work? Weight management Physical health Psychological health Nutritional adequacy

© 2007 Thomson - Wadsworth Weight Management YES! “Listening to body signals in determining what, when, and how much to eat is associated with lower body mass.” (Tylka, 2006) Those scoring higher in “Intuitive Eating” had lower BMI values. (Hawks & Smith 2006)

© 2007 Thomson - Wadsworth Physical Health YES! “Size Acceptance and Intuitive Eating Improve Health for Obese, Female Chronic Dieters” (Bacon et al 2005) HAES group maintained weight, improved cholesterol and blood pressure, and sustained improvements. Diet group showed initial weight loss and metabolic improvement, but by 2 years weight was regained and little improvement was sustained.

© 2007 Thomson - Wadsworth Psychological Health YES! HAES vs dieters study (Bacon et al, 2005) Depression: both improved, HAES sustained, diet group did not Self-esteem: HAES group improved, diet group worsened Higher “intuitive eating” scores associated with higher levels of psychological health (Tylka 2006) Self-esteem Satisfaction with life, optimism, proactive coping Eating disorder symptomatology

© 2007 Thomson - Wadsworth Nutritional Adequacy YES! Intuitive eating correlated with variety in intake. No correlation between intuitive eating and % junk food consumed. Intuitive eating associated with greater pleasure in eating. (Hawks & Smith 2006)

© 2007 Thomson - Wadsworth Strive for overall wellness Get adequate sleep Practice stress and time management Be physically active Engage social support

© 2007 Thomson - Wadsworth EAT WHAT YOU WANT … … when you are truly hungry. Stop when you are full. And eat exactly what appeals to you. Do this instead of any diet, and you are likely to maintain a healthy weight and avoid eating disorders. (National Eating Disorders Association, 2002)