Chapter 9: Energy Balance, Weight Management, and Eating Disorders; Exercise

Obesity The DGAs consider obesity as the #1 health threat facing U.S. Obesity: 69% of adults 17% of children Risk factor for at least 30 chronic diseases Heart disease Stroke Type 2 diabetes Certain cancers Osteoarthritis

What Is a Healthful Body Weight? A healthful weight: is appropriate for your age is consistent with family history and genetics is maintained without constant dieting is compatible with normal blood pressure, lipid levels, and glucose tolerance promotes good eating habits and allows for regular physical activity is acceptable to you

What Is a Healthful Body Weight? Underweight: having too little body fat to maintain health Overweight: having a moderate amount of excess body fat Obesity: having an excess of body fat that adversely affects health Morbid obesity: body weight exceeding 100% of normal, creating very high risk for serious health complications

Gaining or Losing Weight Whether a person gains or loses weight depends on: energy intake vs. energy expenditure* genetic factors childhood weight behavioral factors social factors

Energy Imbalance: Weight Loss

Energy Imbalance: Weight Gain

Energy Balance: Weight Maintenance

Calories Out: Energy Expenditure 3 ways body uses energy: ①Basal metabolic rate (BMR) ②Physical activity ③Thermic effect of food (TEF)

Basal Metabolic Rate (BMR) The majority of calories burned daily Calories that are used for involuntary activities: Heartbeat Breathing Nerve impulse transmission Tissue growth and repair Kidney function These are calories needed to sustain life while at rest BMR is highly variable between people

Factors Affecting BMR Factors That Increase BMRFactors That Decrease BMR More muscle massLess muscle mass Being tallerBeing shorter Being maleBeing female Younger ageOlder age Regular meal consumption (TEF)Skipping meals, fasting, dieting Elevated thyroid hormoneDecreased thyroid hormone Exercise (increased muscle mass)Sleep (BMR is at its lowest) Exposure to hot/cold temperatures Pregnancy & lactation Fever Stress Some drugs: tobacco, caffeine

Physical Activity Calories that are used for voluntary activities Amount used depends on How many muscles used How frequently muscles are used How long muscles are used Personal fitness level, body weight, & total muscle mass Type of activity DGAs recommend aerobic exercise: 2.5 hours of moderate intensity OR 75 minutes of vigorous intensity

Physical Inactivity % Map 2012 The darker the color, the less physical activity Source:

Thermic Effect of Food (TEF) Calories that are used to digest, absorb, transport, store, and metabolize food consumed More calories used for protein, fewer for fat Negligible when it comes to weight loss No foods provide “negative” calories Some are just low calorie

Total Energy Expenditure (TEE)

Out of Balance/Evaluating Body Weight Overweight Obese Underweight Assessment Tools: Scale Body Mass Index (BMI) Body composition estimation Body fat distribution

Evaluating Body Weight Body mass index (BMI) Compares weight to height Indication of a person's overall health BMI values below 18.5 or above 30 indicate increased risk of mortality Calculate your BMI… To square height: inches × inches Or meters x meters

What Is a Healthful BMI? Underweight-BMI below 18.5 Normal-BMI 18.5 to 24.9 Overweight-BMI 25.0 to 29.9 Obesity-BMI 30 to 39.9 Morbid obesity -BMI 40+

Measuring Body Mass Index (BMI)

BMI and Disease Risk ©2001 Brooks/Cole, a division of Thomson Learning, Inc. Thomson Learning ™ is a trademark used herein under license.

BMI and Disease Risk BMI of Overweight High blood pressure High cholesterol Type 2 diabetes Heart disease Sleep apnea Stroke Gallstones/kidney stones Osteoarthritis Certain cancers BMI of 30+ Obese All from the left side Kidney disease Liver disease Pregnancy complications Poor female reproductive health Restricted mobility Bladder problems % greater risk of premature death

BMI Limitations Not accurate for everyone Does not tell if weight comes more from fat or muscle Does not tell where on the body fat is located

Evaluating Body Weight Body composition Measurement of body fat and lean body mass Healthy body fat range: 10-20% men; 18-25% women Excess body fat elevates disease risk 2 types of body fat Essential Storage

Body Composition Assessment 1. Hydrostatic (Underwater) Weighing Bone & muscle denser than water Fat floats Person is submerged underwater and empties his/her lungs of air. Gold standard Based on Archimedes’ PrincipleArchimedes’ Principle

Body Composition Assessment 2. Skinfold Measurement Several areas are measured using calipers, then measurements are input into a formula to determine percent body fat. Requires a skilled technician

Body Composition Assessment 3.Bioelectrical Impedance (BIA) Water is a great conductor of electricity Lean mass contains more water than fat mass. More lean mass = more water = less resistance The greater the amount of water in a person's body, the easier it is for the current to pass through it. The more fat, the more resistance to the current.

Body Composition Assessment 4. Bod Pod Uses air displacement instead of water displacement Determines person’s volume based on pressure (input into equation) Accurate

Body Composition Assessment 5. DEXA Uses x-rays to differentiate between fat, muscle, and bone tissue Person lies on a table, so must be able to fit on it for most accurate result Person must stay in position and be still

Evaluating Body Shape Fat distribution pattern Measured by waist-to- hip ratio Apple-shaped fat patterning Android Abdominal fat Pear-shaped fat patterning Gynoid Hip/thigh fat

Body Fat Location Distribution of fat may be more important than fatness alone Fat patterns determined by: Waist-to-Hip Ratio Apple shaped Upper body obesity Increased risk for chronic diseases Pear shaped Lower body obesity No significant increased risk for chronic diseases

Body Fat Location Waist-to-hip ratio: Waist circumference ÷ hip circumference Female < 0.8 Male < 0.9 Waist circumference alone can determine risk Female ≤ 35 inches Male ≤ 40 inches Numbers greater than these levels indicate an apple shape

Most Americans are: Overweight/obese! 34% of U.S. adults are overweight (~76 million), 35% are obese (~79 million). This means that ~155 million people in America are overweight/obese. Source: National Institutes of Health

Obesity Prevalence has increased dramatically Rates higher among certain ethnic groups As obesity rises, so do diseases associated with it CDC maps presented next show how obesity and type 2 diabetes are highly correlated

CDC’s Division of Diabetes Translation. National Diabetes Surveillance System available at Obesity (BMI≥30 kg/m 2 ) Diabetes <4.5% Missing data 4.5%–5.9% 6.0%–7.4% 7.5%–8.9% ≥9.0% 18.0%–21.9% <14.0% Missing Data 14.0%–17.9% 22.0%–25.9%≥26.0% Age-Adjusted Prevalence of Obesity and Diagnosed Diabetes Among U.S. Adults 1994

CDC’s Division of Diabetes Translation. National Diabetes Surveillance System available at Obesity (BMI≥30 kg/m 2 ) Diabetes <4.5% Missing data 4.5%–5.9% 6.0%–7.4% 7.5%–8.9% ≥9.0% 18.0%–21.9% <14.0% Missing Data 14.0%–17.9% 22.0%–25.9%≥26.0% Age-Adjusted Prevalence of Obesity and Diagnosed Diabetes Among U.S. Adults 2004

CDC’s Division of Diabetes Translation. National Diabetes Surveillance System available at Obesity (BMI≥30 kg/m 2 ) Diabetes <4.5% Missing data 4.5%–5.9% 6.0%–7.4% 7.5%–8.9% ≥9.0% 18.0%–21.9% <14.0% Missing Data 14.0%–17.9% 22.0%–25.9%≥26.0% Age-Adjusted Prevalence of Obesity and Diagnosed Diabetes Among U.S. Adults 2010

Age-Adjusted Prevalence of Obesity and Diagnosed Diabetes Among U.S. Adults Aged 18 Years or older Obesity (BMI ≥30 kg/m 2 ) Diabetes No Data 26.0% No Data 9.0% CDC’s Division of Diabetes Translation. National Diabetes Surveillance System available at

23 states >25% obesity 18 states >30% obesity 2 states ≥35% obesity Mississippi & West Virginia South has the highest (30.2%) and West has the lowest (24.9%) prevalence Source:

Obesity in 2013

Obesity Causes Not just one cause ①Eating more calories than expended ②Environment  Less activity  Higher fat and calorie foods convenient/cheap ③Social relationships ④Genetics  Set point theory  Number of adipose cells ⑤Food addiction

Weight Management Are you truly hungry, or is it just appetite? Hunger The physiological drive to eat Most foods will satisfy Appetite The psychological desire to eat Want of a specific food Common to have appetite without hunger

Weight Management Are you really still hungry, or are you actually full? It takes 20 minutes for the brain to receive satiation signals Satiation: feeling of fullness that ends eating Satiety: length of time fullness lasts between meals High fiber foods promote satiation and satiety

FAD Diets Problems include: Too few calories (lowers BMR) Limited food choices Costly food and/or supplement purchases required Unqualified authors No help provided for lasting behavioral change Diets usually short-term No exercise guidance (loss of muscle mass) Unrealistic expectations Weight regain

Healthful Weight Change ①gradual change in energy intake ①Decrease no more than 500 kcal/day ②Watch portion sizes and beverages ②regular and appropriate physical exercise ①Include weight training to reduce muscle loss ②Include aerobic activity to use more kcals ③application of behavior modification techniques ①See Figure 9.8 on page 357

Obesity Treatments for obesity may include: Reduced-energy diet, increased level of exercise, behavior modification Prescription drugs Surgery – for morbidly obese Vertical sleeve gastrectomy Gastric banding Gastric bypass

Vertical Sleeve Gastrectomy

Gastric Bypass and Gastric Banding

Gastric Bypass Gastric Bypass Video Not complication-free! Diarrhea Gallstones More surgery due to complications Nutrient malabsorption Ulcers Thinning hair Loose skin

Disordered Eating Disordered eating: variety of abnormal or atypical eating behaviors used to reduce weight Eating disorder: psychiatric condition involving extreme body dissatisfaction and long-term eating patterns harming the body An extreme form of disordered eating

Eating Disorders Two common eating disorders: Anorexia nervosa: disorder of self-starvation eventually leading to severe nutrient deficiency Bulimia nervosa: disorder characterized by extreme overeating followed by compensatory behaviors to prevent weight gain

Anorexia Nervosa Symptoms  Extremely restrictive eating practices  Self starvation  Fear eating in public or socially  Self-starvation  Intense fear of weight gain Unwilling to maintain normal weight  Amenorrhea: no menstrual periods for at least 3 consecutive months  Unhealthful body image

Anorexia Nervosa

Anorexia Complications Heart failure Kidney failure Pneumonia Heart problems GI tract problems Anemia Excessive tiredness Dry skin Brittle nails Loss of hair on head Growth of fine body hair Pancreatitis Liver damage Insomnia Dental problems Hypoglycemia Bruising easily

Bulimia Nervosa Bulimia nervosa: disorder characterized by binge eating followed by purging  Binge eating: eating a large amount of food in a short period of time  Feelings of loss of control  Purging: an attempt to rid the body of unwanted food by vomiting, laxatives, fasting, excessive exercise, or other means  Unhealthful body image  Weight may appear normal or even overweight

Bulimia Complications Stomach rupture Heart failure Irregular periods Addictions Psychiatric illness Suicide Electrolyte imbalance Worn tooth enamel Swollen neck glands Inflammed throat Gastroesophageal reflux Kidney problems Severe dehydration

Problems related to Bulimia

ED Risk Factors ①Dieting ①Perception of overweight ②Cultural pressure ①Thin = beautiful = successful ③Body dissatisfaction ①A poor body image ②May result is body dysmorphic disorder ④Self-esteem ⑤Family ⑥Athletics ①Female athlete triad

Treatment for Eating Disorders Successful treatment for eating disorders usually involves a team approach, including: Patient Physician Nutritional and psychiatric counselors Coach – if in sports Family and friends

Exercise

Benefits of Exercise Raises HDL cholesterol Lowers blood pressure Helps prevent Type 2 diabetes Some cancers Reduces stress Helps people meet dietary needs Weight bearing exercise: helps prevent osteoporosis Preserves muscle mass when losing weight

Exercise Recommendations Includes fitness The ability to be physically active without excess fatigue For stretching Warm up muscles for 5-10 minutes before stretching Hold for seconds and repeat 2-4 times Incorporate into all workouts For cardiovascular benefits 3-5 days/week of moderately intense activity minutes each session Can be continuous or intermittent For strength training 2 non-consecutive days/week Perform 8-10 reps each of 8-10 different exercises

Strength Training Benefits Builds muscle mass Increased BMR Weight control Builds and maintains bones Prevents injury Improves daily function activities Enhances sport performance Prevents chronic diseases