chapter six: maintaining a healthy weight

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Chapter Six: Maintaining a Healthy

Weight


Defining Overweight and Obesity Desirable weight = weight range deemed appropriate for people, taking into consideration gender, age, and frame size

Overweight = a person’s excess fat accumulation results in body weight that exceeds desirable weight by 1-19%

Obesity = a person’s body weight is 20% or more above desirable weight


Rates of Overweight and Obesity (Adult Americans)


Obesity and Disease Problems caused or complicated by obesity:

Increased surgical risk Hypertension Heart disease Arthritis Stroke Type 2 diabetes Cancer Joint deterioration

Fat accumulation in the abdomen (“apple” shape) is associated with greater health risks than fat accumulation in the hips (“pear” shape)


Sociocultural Standards for Weight

Body image: Subjective perception of how one’s body appears to oneself and others

What is today’s Western cultural standard of the ideal body? Hourglass shape? Athletic? How does it differ by gender?

Body image dissatisfaction affects self-concept More women than men are dissatisfied with their weight


Measuring and Assessing Weight and Body Fat Composition Body mass index (BMI) Height/weight tables Waist and hip measurement Appearance Home scale Body fat measurement

Electrical impedance Bod Pod Skinfold measurements Hydrostatic weighing


Body Mass Index (BMI) A mathematical calculation based on weight and height used to determine desirable body weight Weight (kg) ÷ [Height (m)]2

Classification Normal: 18.5-24.9 Overweight: 25.0-29.9 Obese: ≥30 Extreme obesity: ≥40


Other Methods used to Assess Weight Height/ Weight Tables

Used to determine ideal weight based on gender, height, and frame size

Waist and Hip Measurement Correlation between the amount of fat in the abdominal cavity and serious health risks

Appearance Home Scale


Body Fat Measurement Young adult men

Normal = 10-15% Obese = >25%

Young adult women Normal = 22-25% Obese = >30%


Body Fat Measurement Electrical impedance: Use of a harmless electrical current to calculate percent body fat

Bod Pod: Measurement of air displacement to determine percent body fat

Skinfold measurements: Measurement of the thickness of the fat layer just below the skin; used to calculate percent body fat

Hydrostatic weighing: Weighing the body while it is submerged in water; used to calculate percent body fat


Causes of Obesity

Calorie balance: Energy intake vs. energy output Intake = Output: Calorie balance Intake > Output: Positive calorie balance• Weight gain

Output > Input: Negative calorie balance• Weight loss

Energy needs: Basal metabolic rate (BMR) Activity requirements Thermic effect of food


Causes of Obesity (cont.)

Genetic factors Physiological and hormonal factors Hypothyroidism Hypercellular obesity Hypertrophic obesity

Metabolic factors Set point Adaptive thermogenesis


Causes of Obesity (cont.)

Family, social, and cultural factors

Environmental factors Local environment Packaging and price Unit bias

Psychological factors


Top States with the Highest and Lowest

Obesity Rates


Facts About Weight Loss


Weight Management Strategies: Lifestyle Approaches

Balanced diet supported by portion control

Moderate physical activity 60 minutes/day for weight maintenance 90 minutes/day for weight loss and maintenance

Sleep Lifestyle support and problem solving


Weight Management Strategies: Specific Dietary Approaches

Temporary calorie restriction (“dieting”) Low-calorie foods and controlled serving sizes

Controlled fasting For extreme obesity Often in a hospital setting

Formal or commercial weight reduction programs


Weight Management Strategies: Weight Loss Drugs

OTC drugs and herbal supplements Ephedrine, phenylpropanolamine (now banned)

Caffeine, laxatives Prescription weight loss drugs

Phentermine Sibutramine

Fat-blocking drugs Orlistat

• Prescription Xenical• OTC Alli


Weight Management Strategies: Surgical Interventions

Gastric bypass Gastric sleeve

Gastric band Vertical banded Laproscopic adjustable

Cosmetic Liposuction Abdominoplasty Body wrapping Lipodissolve


Eating Disorders Most eating disorders involve psychological issues as well as inappropriate food choices or eating patterns

Types/categories Anorexia nervosa Bulimia nervosa Binge eating disorder Chewing, spitting out food syndrome Night eating syndrome Body dysmorphic disorder Bigorexia


Anorexia Nervosa Diagnostic criteria:

Body weight 15% or more below desirable weight

Fear of weight gain Distorted body image In women, absence or three of more menstrual periods

In men, decreased sex hormone Serious medical complications, including death

Treatment: Medical and dietary interventions, psychological treatment


Bulimia Nervosa Diagnostic criteria:

Binge eating two or more times/week for at least 3 months

Lack of control over bingeing Inappropriate compensatory behaviors (purging)• Vomiting or use of laxatives, diuretics, or other medications

• Excessive exercise• Fasting

Overconcern with body image Serious medical complications Treatment: nutritional and psychological counseling, medical consultation


Other Eating Disorders Binge eating disorder

Bingeing without compensatory purging Use food to cope; feel out of control during binge

Chewing and spitting out food syndrome Night eating syndrome Body dysmorphic disorder

Preoccupation with an imagined or slight flaw in one’s appearance

Bigorexia Muscle dysmorphia, “Adonis complex” An obsession with getting bigger and more muscular

Thinking that your body is never muscular enough


Chapter Six: Maintaining a Healthy Weight

chapter six: maintaining a healthy weight

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