© McGraw-Hill Companies. All rights reserved. Achieving a Health Weight and Body Composition Chapter 8

© McGraw-Hill Companies. All rights reserved. Achieving a Healthy Weight At any given time, more than one-half of women and one-fourth of men are on a diet At any given time, more than one-half of women and one-fourth of men are on a diet For some people the weight obsession can lead to serious body-image problems, including body dysmorphic disorder (BDD) For some people the weight obsession can lead to serious body-image problems, including body dysmorphic disorder (BDD) The number of people who would benefit from a weight-loss program is at an all-time high The number of people who would benefit from a weight-loss program is at an all-time high

© McGraw-Hill Companies. All rights reserved. Healthy Aspects of Obesity Coronary heart disease Coronary heart disease Stroke Stroke Hypertension Hypertension LDL cholesterol LDL cholesterol Diabetes Diabetes Psychological distress Psychological distress Gallbladder disease Gallbladder disease Osteoarthritis Osteoarthritis Sleep apnea Sleep apnea Some cancers Some cancers

© McGraw-Hill Companies. All rights reserved. Obesity Trends Among U.S. Adults

© McGraw-Hill Companies. All rights reserved. Development of Obesity Obesity occurs when the 30 to 40 million adipose (fat) cells in the body increase in size (hypertrophy), number (hyperplasia), or both Obesity occurs when the 30 to 40 million adipose (fat) cells in the body increase in size (hypertrophy), number (hyperplasia), or both Gender differences in fat storage Gender differences in fat storage –Males- upper half of body (android) –Females- lower half of body (gynoid) Biological factors that influence obesity are age, metabolism, gender, disease, heredity, and set point Biological factors that influence obesity are age, metabolism, gender, disease, heredity, and set point

© McGraw-Hill Companies. All rights reserved. Adipose Cell Deposits

© McGraw-Hill Companies. All rights reserved. Causes of Obesity Heredity influences both body weight and body shape Heredity influences both body weight and body shape –Ectomorph –Endomorph –Mesomorph The set point theory suggests that the body works to maintain a certain weight no matter what a person does The set point theory suggests that the body works to maintain a certain weight no matter what a person does

© McGraw-Hill Companies. All rights reserved. Overeating consuming more calories than are required by the body Most experts view high dietary fat intake as the major factor in obesity Most experts view high dietary fat intake as the major factor in obesity Calories from fat appear to convert to body fat more readily than calories from carbohydrates and protein Calories from fat appear to convert to body fat more readily than calories from carbohydrates and protein Portion size Portion size

© McGraw-Hill Companies. All rights reserved. Overeating and Inactivity People cannot eat as much as they want to just because a food is fat free People cannot eat as much as they want to just because a food is fat free Modern conveniences and labor- saving devices have resulted in less physical activity Modern conveniences and labor- saving devices have resulted in less physical activity A sedentary lifestyle is partially responsible for the obesity in America A sedentary lifestyle is partially responsible for the obesity in America Physical exercise is vital for weight maintenance Physical exercise is vital for weight maintenance

© McGraw-Hill Companies. All rights reserved. Inactivity Some experts view lack of physical activity as the distinguishing factor that separates the obese from those of normal weight Some experts view lack of physical activity as the distinguishing factor that separates the obese from those of normal weight Exercise alone is not a major component in weight loss, but it is the most important component in weight gain Exercise alone is not a major component in weight loss, but it is the most important component in weight gain

© McGraw-Hill Companies. All rights reserved. Strategies for Weight Management or Weight Loss The loss of one pound of body fat requires a deficit of 3500 calories The loss of one pound of body fat requires a deficit of 3500 calories A desirable long-term goal for losing weight is 1 to 2 pounds a week until 10% of total body weight is lost A desirable long-term goal for losing weight is 1 to 2 pounds a week until 10% of total body weight is lost A six-month maintenance program should follow weight loss before losing more A six-month maintenance program should follow weight loss before losing more Weight loss should be a combination of restricting calories and increasing caloric expenditure Weight loss should be a combination of restricting calories and increasing caloric expenditure

© McGraw-Hill Companies. All rights reserved. Strategies for Weight Management or Weight Loss (2) Dieting Dieting –the method of choice for most people to lose weight –Only 5% of dieters successfully lose and maintain their weight loss for one year –Weight cycling (yo-yo dieting) usually results in a greater weight gain following a loss period and increases the risk of death

© McGraw-Hill Companies. All rights reserved. Strategies for Weight Management or Weight Loss (3) Caloric intake should not drop below 1200 per day for women or 1500 per day for men Caloric intake should not drop below 1200 per day for women or 1500 per day for men Popular Diets Popular Diets –Potentially hazardous Characteristics of fad diets Characteristics of fad diets –Promote quick results; focus on eating one type of food or excluding an entire food group, rarely emphasize permanent lifestyle changes

© McGraw-Hill Companies. All rights reserved. Strategies for Weight Management or Weight Loss (4) Low fat diets Low fat diets –Americans are consuming fewer fat calories but more total calories and are getting heavier Very low calorie diets (VLCDs) have fewer than 800 calories a day and should be viewed as medical intervention Very low calorie diets (VLCDs) have fewer than 800 calories a day and should be viewed as medical intervention Americans are consuming fewer fat calories but more total calories and are getting heavier Americans are consuming fewer fat calories but more total calories and are getting heavier

© McGraw-Hill Companies. All rights reserved. Strategies for Weight Management or Weight Loss (5) Overcompensatory eating is when the consumption of low-fat foods leads to an increase in total calories Overcompensatory eating is when the consumption of low-fat foods leads to an increase in total calories Increases in portion sizes of foods in restaurants and in the grocery contribute to greater food consumption Increases in portion sizes of foods in restaurants and in the grocery contribute to greater food consumption Diet drugs offer only a temporary solution and side effects can be deadly Diet drugs offer only a temporary solution and side effects can be deadly

© McGraw-Hill Companies. All rights reserved. Strategies for Weight Management or Weight Loss (6) Herbal remedies are unregulated and when taken in large, concentrated doses should be viewed as drugs Herbal remedies are unregulated and when taken in large, concentrated doses should be viewed as drugs The optimal approach to weight loss combines mild caloric restriction with regular physical activity The optimal approach to weight loss combines mild caloric restriction with regular physical activity Fasting and modified fasts can be harmful especially if done for a prolonged period of time Fasting and modified fasts can be harmful especially if done for a prolonged period of time

© McGraw-Hill Companies. All rights reserved. Mayo Clinic Healthy Weight Pyramid

© McGraw-Hill Companies. All rights reserved. Physical Activity Physical activity and dieting should yield a daily caloric deficit of 300 to 1000 calories

© McGraw-Hill Companies. All rights reserved. Physical Activity Basal metabolic rate (BMR) is the energy required to sustain life when the body is rested and fasting Basal metabolic rate (BMR) is the energy required to sustain life when the body is rested and fasting Persons who are deconditioned need to start slowly and progress gradually Persons who are deconditioned need to start slowly and progress gradually Increased muscle tissue raises BMR Increased muscle tissue raises BMR People who lose weight and keep it off almost always exercise daily People who lose weight and keep it off almost always exercise daily Low intensity exercise burns more fat calories Low intensity exercise burns more fat calories

© McGraw-Hill Companies. All rights reserved. Guidelines To reduce risk of chronic diseases in adulthood: 30min of moderate physical activity daily To reduce risk of chronic diseases in adulthood: 30min of moderate physical activity daily To prevent unhealthy weight gain in adulthood: 60min of moderate to vigorous physical activity on most days To prevent unhealthy weight gain in adulthood: 60min of moderate to vigorous physical activity on most days To sustain weight loss in adulthood: 60min moderate daily physical activity To sustain weight loss in adulthood: 60min moderate daily physical activity

© McGraw-Hill Companies. All rights reserved. Eating Disorders Anorexia nervosa Anorexia nervosa –the refusal to maintain minimally normal weight for age and height. –characterized by the refusal to eat Bulimia nervosa Bulimia nervosa –alternates bingeing with purging (Symptoms of disordered eating are also serious Binge-eating disorder Binge-eating disorder –Consuming large amounts of food in one sitting –Lack of control The Female Athlete Triad is common among young athletes The Female Athlete Triad is common among young athletes –Disordered eating, amenorrhea, osteoporosis

© McGraw-Hill Companies. All rights reserved. Principles of Weight Management Avoiding an obsession with body weight Avoiding an obsession with body weight Avoiding fad diets Avoiding fad diets Avoiding fasting and restrictive dieting Avoiding fasting and restrictive dieting Developing a plan Developing a plan Being physically active Being physically active Making gradual lifestyle changes Making gradual lifestyle changes They include: They include:

© McGraw-Hill Companies. All rights reserved. Achieving a Health Weight and Body Composition Chapter 8