Chapter 8

• Obesity prevalence has nearly tripled since 1975.
• Globally, the overweight population now rivals the underfed and underweight.

Nutrition Requirements

• Aside from water and caloric energy, the body needs 46 nutrients.
• These nutrients are grouped into proteins, fats, carbohydrates, vitamins, and minerals.
• Poor nutrition is linked to 5 of the 10 leading causes of death, including heart disease, cancer, stroke, diabetes, and atherosclerosis.
• Current dietary guidelines suggest limiting added sugar and saturated fat to no more than 10% of total daily calories each.

Chronic Conditions

• The number of people with multiple chronic conditions has increased across genders, races, ethnicities, and income groups.
• Common combinations of chronic conditions include hypertension and diabetes, hypertension and heart disease, and hypertension and cancer.

Basal Metabolic Rate

• Basal metabolic rate (BMR) is affected by age, gender, current weight, and activity level.
• The body balances energy intake and expenditure, supporting the idea of a body weight set point.
• The number of fat cells, or adipocytes, in a person's body, never decreases once increased.
• Adipocytes are specialized cells that store energy as lipids and regulate metabolism and hormones.

Appetite and Weight Regulation

• The arcuate nucleus is the central regulator of short-term appetite and long-term body weight.
• Ghrelin and peptide Y (PYY) are hormones associated with short-term feeding behaviors.
• Leptin, and to a lesser extent, insulin, are involved in long-term weight maintenance.
• Leptin, primarily produced by adipose tissue, regulates energy balance by signaling to the brain when enough fat is stored, reducing appetite.

Obesity Risks and Factors

• Obesity is a risk factor for many diseases, second only to smoking as a behavioral factor in mortality rates.
• Obesity is defined by a body mass index (BMI) of 30 or higher, indicating excessive body fat accumulation.
• Overweight is defined as having a BMI between 25 and 29.9, indicating more body weight than is considered healthy for a given height.
• Body mass index (BMI) is the most common measure of obesity.
• Abdominal obesity is excess fat accumulation in the abdominal area, measured by waist circumference or waist-to-hip ratio, associated with a higher risk of metabolic diseases.
• Abdominal fat (male pattern) poses greater health risks than lower-body fat (female pattern).
• Weight cycling, or the repeated loss and regain of body weight, may be more harmful than maintaining a somewhat high but stable weight.
• Higher BMI increases the prevalence of metabolic syndrome.
• Susceptibility to obesity is polygenic, with the FTO gene potentially acting as a "genetic switch" for calorie burning or storage.
• Weight stigma includes negative attitudes, stereotypes, and discrimination toward individuals based on their weight, impacting psychological and physical health.
• Stress eating can increase long-term disease risk by initiating unhealthy eating habits.
• Poverty income ratio measures income relative to the federal poverty threshold, calculated by dividing household income by the poverty threshold for household size and composition.
• Obesity has an inverse relationship with education and occupation level.
• Access to healthy foods can mitigate the dietary risks of low income.
• Competitive foods, like snacks from vending machines, are sold in schools outside regulated meal programs, competing with healthier school meals.

Obesity Treatment and Prevention

• Successful diets often involve post-treatment support like social support, exercise, or continued therapy contact.
• Behavior modification, emphasizing self-monitoring, is commonly used in modern weight-loss programs.
• Maintaining healthy food choices, self-monitoring, and preventing obesity are especially challenging due to obesogenic environments.
• Intuitive eating is a self-care approach that emphasizes listening to internal hunger and fullness cues, promoting a healthy relationship with food.

Eating Disorders

• Anorexia nervosa involves refusing to maintain a healthy weight, intense fear of weight gain, and body image disturbance.
• Anorexia nervosa is characterized by extreme food restriction, an intense fear of gaining weight, and a distorted body image, leading to severe weight loss and health complications.
• Bulimia nervosa includes bingeing followed by purging, via self-induced vomiting or laxatives.
• Bulimia nervosa is marked by binge eating episodes followed by compensatory behaviors like self-induced vomiting, excessive exercise, or laxative use to prevent weight gain.
• Binge-eating disorder, the most prevalent, features a lack of purging but feelings of loss of control and distress.
• Binge eating disorder is characterized by recurrent episodes of consuming large amounts of food in a short period, often with a feeling of loss of control and distress, but without compensatory behaviors like purging.
• Muscle dysmorphia is a subtype of body dysmorphic disorder (BDD) where individuals obsessively believe their muscles are too small, leading to excessive exercise, strict dieting, and possible steroid use.

Eating Disorder Prevalence

• Eating disorders affect both women and men.
• Males and females with eating disorders commonly share issues like body image dissatisfaction, age of onset, morbidity, and prognosis.
• Differences may arise in the factors leading to disordered eating, weight-control methods, and help-seeking behavior.

Eating Disorder Factors and Therapy

• Eating disorders are multifactorial, influenced by biological, psychological, social, and cultural elements.
• Abnormal neurotransmitter levels in areas regulating reward, emotion, planning, and interoception may be associated with eating disorders.
• Interoception is the ability to sense internal bodily signals to help regulate physiological and emotional states.
• Treatments address both behavior and attitudes perpetuating disordered eating.
• Cognitive-behavioral therapy is widely used for anorexia and bulimia, targeting flawed thinking about food, weight, and body image.