1. Managing Your Weight

2. Chapter 10 Managing Your Weight
Learning Outcomes:
Describe the relationship between calories and weight
Explain theories and evidence as to why people become overweight
Discuss the eating disorders, their origins, and their treatment

3. A Nation at Risk
2 out of 3 adults in the United States are overweight.
Over ½ of those overweight are obese
Obesity is a major risk factor for many serious health problems including cardiovascular disease, diabetes, respiratory illnesses, and some forms of cancer.
Life expectancy is shortened by 6-7 years

4. Calories and Weight: A Balancing Act
Energy In – food energy (calories) we consume
Energy Out – energy expended
Maintaining normal body functions
Digestion, breathing, circulation
Through physical activity and exercise

5. Energy Expended Metabolic Rates – how fast we burn calories
Basal Metabolic Rate (BMR)
the minimum amount of energy needed to maintain body functions apart from digestion
Resting Metabolic Rate (RMR)
The minimum energy that the body requires to maintain body functions including digestion
Factors affecting metabolic rates:
Age
Gender
Weight
Activity Level

6. Weight Indices BMI (body mass index) Body Composition
Broad stroke measure - Based on height/weight
BMI to 24.9 considered healthy range
Does not take age, gender, or lean body mass into account
Body Composition
More precise measure of body fat%
Obese standards >24% males >33% females
Waist Circumference, Waist-to-Hip Ratio
Men >40”, ratio>1; Women >35”, ratio>0.8 may be at higher health risk

7. Factors in Becoming Overweight
Heredity
Genetic contribution to body shape, regulation of the production of leptin – “signals fullness”
Metabolic Factors
Set point theory: brain regulates “predetermined weight” – thermostat analogy
Set point doesn’t lower with dieting alone, need physical activity including muscle fitness
Muscle tissue - higher metabolic rate than fat, even at rest

8. Factors in Becoming Overweight
Fat Cells
Obese people have billions more fat cells than people of average rate
Heredity affects initial number of fat cells, but early dietary habits contribute as well
Fat cells are not shed when losing weight, continue to send signals to hypothalamus
Women have higher percentage of essential fat then men; makes it easier for men to keep excess weight off

9. Factors in Becoming Overweight
Physical Inactivity
Inactivity contributes to weight gain and people tend to be less active as they gain weight
Problem Eating Habits
Eating fast – it takes the brain 15 minutes to catch up with the stomach
Fast Food
Food–Related Cues
Emotional Eating
Celebrations, “drown our sorrows”

10. Eating Disorders
Characterized by persistent, gross disturbances in eating patterns
More than ½ of teenage girls and nearly 1/3 of teenage boys use unhealthful methods to try and control weight including fasting, skipping meals, smoking, purging by vomiting or laxatives
Incidences of eating disorders has increased markedly in recent years.
Afflicts mainly women during adolescence and young adulthood
Women tend to be perfectionists about their bodies

11. Eating Disorders Anorexia Nervosa
characterized by the maintenance of an unusually low and unhealthy body weight and accompanied by an intense fear of gaining weight, a distorted body image, and in females, an absence of menstruation
Females can drop 25% or more of their weight within a year triggering abnormalities and health problems
Common trigger seems to be onset of puberty and corresponding weight gain

12. Eating Disorders Bulimia Nervosa
Characterized by repeated episodes of binge eating followed by purging, and accompanied by persistent fears of gaining weight
Various methods of purging: vomiting, use of laxatives, strict dieting or fasting, prolonged demanding exercise regimens
Triggers hormonal imbalances

13. Origins of Eating Disorders
Different explanations
may symbolize a young woman’s efforts to cope with sexual fears
Dysfunctional families
Starts as form of rebellion against parents who are obsessed with getting their children to eat
History of child abuse – higher risk
Social-cultural factors – slimness is idealized
Involvement in activities with weight limits
Genetic factors – personality traits

14. Treatment for Eating Disorders
Those who become dangerously thin or malnourished are hospitalized and force-fed if necessary.
Use of drugs that curb the actions of serotonin
Antidepressants
Psychological approaches
Behavior modification
Response prevention
Psychodynamic treatment
Family therapy