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Achieving a Health Achieving a Health Weight and Body Weight and Body

CompositionComposition

Chapter 8Chapter 8

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Achieving a Healthy WeightAchieving a Healthy Weight

At any given time, more than one-half of At any given time, more than one-half of women and one-fourth of men are on a women and one-fourth of men are on a diet diet

For some people the weight obsession can For some people the weight obsession can lead to serious body-image problems, lead to serious body-image problems, including body dysmorphic disorder (BDD) including body dysmorphic disorder (BDD)

The number of people who would benefit The number of people who would benefit from a weight-loss program is at an all-from a weight-loss program is at an all-time hightime high

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Healthy Aspects of ObesityHealthy Aspects of Obesity

Coronary heart Coronary heart diseasedisease

StrokeStroke Hypertension Hypertension LDL cholesterolLDL cholesterol Diabetes Diabetes

Psychological Psychological distress distress

Gallbladder Gallbladder disease disease

Osteoarthritis Osteoarthritis Sleep apnea Sleep apnea Some cancersSome cancers

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Obesity Trends Among U.S. Obesity Trends Among U.S. AdultsAdults

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Development of ObesityDevelopment of Obesity

Obesity occurs when the 30 to 40 million Obesity occurs when the 30 to 40 million adipose (fat) cells in the body increase in adipose (fat) cells in the body increase in size (hypertrophy), number (hyperplasia), or size (hypertrophy), number (hyperplasia), or both both

Gender differences in fat storageGender differences in fat storage– Males- upper half of body (android)Males- upper half of body (android)– Females- lower half of body (gynoid)Females- lower half of body (gynoid)

Biological factors that influence obesity are Biological factors that influence obesity are age, metabolism, gender, disease, heredity, age, metabolism, gender, disease, heredity, and set pointand set point

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Adipose Cell DepositsAdipose Cell Deposits

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Causes of ObesityCauses of Obesity

Heredity influences both body Heredity influences both body weight and body shape weight and body shape – EctomorphEctomorph– EndomorphEndomorph– MesomorphMesomorph

The set point theory suggests The set point theory suggests that the body works to maintain that the body works to maintain a certain weight no matter what a certain weight no matter what a person does a person does

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Overeating Overeating consuming more calories than are required by the bodyconsuming more calories than are required by the body

Most experts view high Most experts view high dietary fat intake as the dietary fat intake as the major factor in obesity major factor in obesity

Calories from fat appear to Calories from fat appear to convert to body fat more convert to body fat more readily than calories from readily than calories from carbohydrates and protein carbohydrates and protein

Portion sizePortion size

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Overeating and InactivityOvereating and Inactivity

People cannot eat as much as People cannot eat as much as they want to just because a they want to just because a food is fat freefood is fat free

Modern conveniences and Modern conveniences and labor-saving devices have labor-saving devices have resulted in less physical activityresulted in less physical activity

A sedentary lifestyle is partially A sedentary lifestyle is partially responsible for the obesity in responsible for the obesity in America America

Physical exercise is vital for Physical exercise is vital for weight maintenanceweight maintenance

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InactivityInactivity

Some experts view lack of physical Some experts view lack of physical activity as the distinguishing factor that activity as the distinguishing factor that separates the obese from those of separates the obese from those of normal weight normal weight

Exercise alone is not a major Exercise alone is not a major component in weight loss, but it is the component in weight loss, but it is the most important component in weight most important component in weight gain gain

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Strategies for Weight Strategies for Weight Management or Weight Management or Weight

LossLoss The loss of one pound of body fat requires a The loss of one pound of body fat requires a

deficit of 3500 calories deficit of 3500 calories A desirable long-term goal for losing weight A desirable long-term goal for losing weight

is 1 to 2 pounds a week until 10% of total is 1 to 2 pounds a week until 10% of total body weight is lost body weight is lost

A six-month maintenance program should A six-month maintenance program should follow weight loss before losing morefollow weight loss before losing more

Weight loss should be a combination of Weight loss should be a combination of restricting calories and increasing caloric restricting calories and increasing caloric expenditureexpenditure

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Strategies for Weight Strategies for Weight Management or Weight Loss Management or Weight Loss

(2) (2) Dieting Dieting

– the method of choice for the method of choice for most people to lose weightmost people to lose weight

– Only 5% of dieters Only 5% of dieters successfully lose and successfully lose and maintain their weight loss for maintain their weight loss for one year one year

– Weight cycling (yo-yo Weight cycling (yo-yo dieting) usually results in a dieting) usually results in a greater weight gain following greater weight gain following a loss period and increases a loss period and increases the risk of deaththe risk of death

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Strategies for Weight Strategies for Weight Management or Weight Loss Management or Weight Loss

(3)(3) Caloric intake should not drop below 1200 Caloric intake should not drop below 1200

per day for women or 1500 per day for per day for women or 1500 per day for men men

Popular DietsPopular Diets– Potentially hazardous Potentially hazardous

Characteristics of fad dietsCharacteristics of fad diets– Promote quick results; focus on eating one Promote quick results; focus on eating one

type of food or excluding an entire food group, type of food or excluding an entire food group, rarely emphasize permanent lifestyle changesrarely emphasize permanent lifestyle changes

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Strategies for Weight Strategies for Weight Management or Weight Loss Management or Weight Loss

(4)(4) Low fat dietsLow fat diets

– Americans are consuming fewer fat calories Americans are consuming fewer fat calories but more total calories and are getting heavier but more total calories and are getting heavier

Very low calorie diets (VLCDs) have fewer Very low calorie diets (VLCDs) have fewer than 800 calories a day and should be than 800 calories a day and should be viewed as medical intervention viewed as medical intervention

Americans are consuming fewer fat Americans are consuming fewer fat calories but more total calories and are calories but more total calories and are getting heaviergetting heavier

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Strategies for Weight Strategies for Weight Management or Weight Loss Management or Weight Loss

(5)(5) Overcompensatory eating is when Overcompensatory eating is when

the consumption of low-fat foods the consumption of low-fat foods leads to an increase in total leads to an increase in total calories calories

Increases in portion sizes of foods Increases in portion sizes of foods in restaurants and in the grocery in restaurants and in the grocery contribute to greater food contribute to greater food consumption consumption

Diet drugs offer only a temporary Diet drugs offer only a temporary solution and side effects can be solution and side effects can be deadlydeadly

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Strategies for Weight Strategies for Weight Management or Weight Loss Management or Weight Loss

(6)(6) Herbal remedies are unregulated Herbal remedies are unregulated

and when taken in large, and when taken in large, concentrated doses should be concentrated doses should be viewed as drugs viewed as drugs

The optimal approach to weight The optimal approach to weight loss combines mild caloric loss combines mild caloric restriction with regular physical restriction with regular physical activity activity

Fasting and modified fasts can be Fasting and modified fasts can be harmful especially if done for a harmful especially if done for a prolonged period of timeprolonged period of time

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Mayo Clinic Mayo Clinic Healthy Weight PyramidHealthy Weight Pyramid

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Physical ActivityPhysical Activity

Physical activity and dieting should Physical activity and dieting should yield a daily caloric deficit of 300 to yield a daily caloric deficit of 300 to

1000 calories1000 calories

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Physical ActivityPhysical Activity

Basal metabolic rate (BMR) is the energy Basal metabolic rate (BMR) is the energy required to sustain life when the body is required to sustain life when the body is rested and fasting rested and fasting

Persons who are deconditioned need to Persons who are deconditioned need to start slowly and progress graduallystart slowly and progress gradually

Increased muscle tissue raises BMR Increased muscle tissue raises BMR People who lose weight and keep it off People who lose weight and keep it off

almost always exercise dailyalmost always exercise daily Low intensity exercise burns more fat Low intensity exercise burns more fat

caloriescalories

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GuidelinesGuidelines

To reduce risk of chronic diseases in To reduce risk of chronic diseases in adulthood: 30min of moderate physical adulthood: 30min of moderate physical activity dailyactivity daily

To prevent unhealthy weight gain in To prevent unhealthy weight gain in adulthood: 60min of moderate to adulthood: 60min of moderate to vigorous physical activity on most daysvigorous physical activity on most days

To sustain weight loss in adulthood: To sustain weight loss in adulthood: 60min moderate daily physical activity60min moderate daily physical activity

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Eating DisordersEating Disorders Anorexia nervosa Anorexia nervosa

– the refusal to maintain minimally normal weight for age and the refusal to maintain minimally normal weight for age and height. height.

– characterized by the refusal to eat characterized by the refusal to eat Bulimia nervosa Bulimia nervosa

– alternates bingeing with purging (Symptoms of disordered alternates bingeing with purging (Symptoms of disordered eating are also seriouseating are also serious

Binge-eating disorderBinge-eating disorder– Consuming large amounts of food in one sittingConsuming large amounts of food in one sitting– Lack of controlLack of control

The Female Athlete Triad is common among young The Female Athlete Triad is common among young athletesathletes– Disordered eating, amenorrhea, osteoporosisDisordered eating, amenorrhea, osteoporosis

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Principles of Weight Principles of Weight Management Management

Avoiding an Avoiding an obsession with obsession with body weightbody weight

Avoiding fad dietsAvoiding fad diets Avoiding fasting Avoiding fasting

and restrictive and restrictive dietingdieting

Developing a plan Developing a plan Being physically Being physically

activeactive Making gradual Making gradual

lifestyle changeslifestyle changes

They include:They include:

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Achieving a Health Weight and Body Achieving a Health Weight and Body CompositionComposition

Chapter 8Chapter 8