Weight Management: Overweight, Obesity, and Underweight

1. Weight Management: Overweight, Obesity, and Underweight Chapter 9

2. Overweight and Obesity • Major health problem in the U.S. • Growing concern worldwide • Prevalence continues to increase • Women, poor, blacks, and Hispanics • Children • BMI of 25 or greater • Epidemic is worldwide • Not merely among industrialized countries

3. Overweight and Obesity

4. Fat Cell Development • Energy in exceeds energy out • Stored in fat cells of adipose tissue • Body fat • Number and size of fat cells • Periods in life when fat cell numbers increase • Cell proliferation • Energy out exceeds energy in • Fat cell size decreases; no change in number

5. Fat Cell Development

6. During growth, fat cells increase in number. When energy intake exceeds expenditure, fat cells increase in size. When fat cells have enlarged and energy intake continues to exceed energy expenditure, fat cells increase in number again. With fat loss, the size of the fat cells shrinks but not the number. Stepped Art Fig. 9-2, p. 273

7. Fat Cell Metabolism • Lipoprotein lipase (LPL) activity • Storage of triglycerides • Obese people vs. lean people • Activity in varying body regions • Men vs. women • Enzyme activity releasing and breaking down fat • Fat oxidation is not efficient

8. Causes of Overweight & Obesity – Genetics & Epigenetics • Causative role of genetics • Genetic influences do seem to be involved • Genetics may determine predisposition to obesity • Genes interact with: • Diet and physical activity • Satiety and energy balance • Human genome

9. Causes of Overweight & Obesity – Genetics & Epigenetics • Obesity gene • Codes for the protein leptin • Acts as a hormone in hypothalamus • Promotes negative energy balance • Suppresses appetite • Increases energy expenditure • Locations of leptin secretion

10. Causes of Overweight & Obesity – Genetics & Epigenetics • Obesity gene • Genetic deficiency of leptin or genetic mutation • Rare • Leptin resistance • Excessive fructose consumption • Roles in the body • Energy regulation • Others

11. Causes of Overweight & Obesity – Genetics & Epigenetics • Adiponectin • Secreted by adipose tissue • Inverse correlation with body fat • Benefits • Ghrelin • Promotes positive energy balance • Inverse correlation with body weight • Roles in the body beyond energy regulation

12. Causes of Overweight & Obesity – Genetics & Epigenetics • PYY • GI cells secrete in proportion to kcalories consumed • Signals satiety and decreases food intake • Ideal diet • Maintain satiating hormones • Minimize appetite stimulating hormones • Low in fat and rich in fiber

13. Causes of Overweight & Obesity – Genetics & Epigenetics

14. Causes of Overweight & Obesity – Genetics & Epigenetics • Uncoupling proteins • Proteins involved in energy metabolism • Two types of fat • White adipose tissue • Brown adipose tissue • Uncoupling proteins found in both types of fat • Influence basal metabolic rate (BMR)

15. Causes of Overweight & Obesity – Environment • Encountered daily circumstances • Interaction between environment and genetics • Overeating • Present and past eating and activity patterns influence current body weight • Availability • Serving sizes • Restaurant food

16. Causes of Overweight & Obesity – Environment • Physical inactivity • Life requires little exertion • Modern technology • Inactivity contributes to weight gain and poor health • Sedentary activities and weight gain • DRI for prevention of weight gain • 60 minutes of moderate activity every day

17. Problems of Overweight and Obesity – Health Risks • Three indicators • BMI • Waist circumference • Disease risk profile • Factors taken into account • Beneficial weight loss • Health status • Motivation

18. Problems of Overweight and Obesity – Health Risks • Overweight in good health • Sometimes health is not the motivation for weight loss • Obese or overweight with risk factors • Two or more risk factors • Obese or overweight with life-threatening condition • Recommendation to lose weight

19. Problems of Overweight and Obesity – Perceptions & Prejudices • Most obese people do not successfully lose weight and maintain the loss • Social consequences • Jobs, school, and in social situations • Psychological problems • Embarrassment • Other feelings

20. Problems of Overweight and Obesity – Perceptions & Prejudices

21. Problems of Overweight and Obesity – Dangerous Interventions • Intervention dangers • Diet books and weight-loss programs • Little success with weight loss maintenance • Fad diets • Weight-loss products • Herbal products • Laws for dietary supplements • Other gimmicks

22. Aggressive Treatments for Obesity – Drugs • Strategies for weight reduction depend on: • Degree of obesity • Risk of disease • Use drugs as part of long-term comprehensive weight-loss programs • Assist with modest weight loss • Four drugs approved by FDA for obesity

23. Aggressive Treatments for Obesity – Drugs • Sibutramine • Suppresses appetite • Side effects • Warning from FDA • Orlistat • Inhibits pancreatic lipase activity in GI tract • Blocks dietary fat digestion and absorption • Side effects

24. Aggressive Treatments for Obesity – Drugs • Phentermine and diethylpropion • Enhance release of neurotransmitter • Norepinephrine • Reduces food intake • Side effects • Other drugs • “Off-label use”

25. Aggressive Treatments for Obesity – Surgery • Clinically severe obesity • 200,000 surgeries performed each year • Reduces food capacity of stomach • Effectively limits food intake • Reduce production of ghrelin • Health-related benefits • Long-term safety and effectiveness • Liposuction

26. Aggressive Treatments for Obesity – Surgery

27. Weight Loss Strategies • Successful strategies • Small changes • Moderate losses • Reasonable goals • Reasonable rate of weight loss • Benefits of modest weight loss • Incorporation of healthy eating and physical activity

28. Weight Loss Strategies

29. Weight Loss Strategies – Eating Plans • Be realistic about energy intake • Provide less energy than is needed • Avoid restrictive eating • Avoid rapid weight loss • Goal: nutritional adequacy without excess • Deficit of 500 to 1000 kcalories per day • Breakfast frequency • Inversely related to obesity

30. Weight Loss Strategies – Eating Plans • Nutritional adequacy • Minimum of 1200 kcalories a day • Eat small portions • Eat less food at each meal • Feel satisfied, not stuffed • Structured meal replacement plans • Lower energy density • Cost

31. Weight Loss Strategies – Eating Plans

32. Weight Loss Strategies – Eating Plans • Remember water • Assistance with weight management • Focus on fiber • Low in energy and high in nutrients • Require effort to eat • Speed of food consumption • Choose fats sensibly • Energy density and satiation

33. Weight Loss Strategies – Eating Plans • Select carbohydrates carefully • Artificial sweeteners • Impact on energy intake • Watch for empty kcalories • Fat, sugar, and alcohol

34. Weight Loss Strategies – Physical Activity • Best approach to weight management • Moderate physical activity plus activities of daily life • Combination of diet and physical activity • Lose more fat • Retain more muscle • Regain less weight • Reduction of abdominal fat

35. Weight Loss Strategies – Physical Activity • kCalorie expenditure • Body weight, intensity, and duration • Greater the energy deficit, greater the fat loss • Discretionary kcalorie allowance • Metabolism • Speeds up with activity • Immediate and long-term benefits

36. Weight Loss Strategies – Physical Activity

37. Weight Loss Strategies – Physical Activity • Body composition • Fat decreases and lean body mass increases • Strength-training exercises • Abdominal fat • Appetite control • Delayed appetite • Inappropriate appetite

38. Weight Loss Strategies – Physical Activity • Psychological benefits • Self-esteem • Choosing activities • Ones you enjoy & are willing to do regularly • Low-to-moderate intensity • 2000 calories per week • Energy-expending daily activities • Spot reducing

39. Weight Loss Strategies – Environmental Influences • Factors surrounding eating experience and the food itself • Atmosphere • Pleasant and comfortable equals more food • Accessibility • Less effort needed to obtain food, more food eaten

40. Weight Loss Strategies – Environmental Influences • Socializing • Duration of meal • Visual cues • Distraction • Distractions • Initiating eating • Interfering with internal controls • Extending duration of eating

41. Weight Loss Strategies – Environmental Influences • Presence • Sight, smell, or thought of food can prompt eating • Multiple choice • Large assortments of foods increase consumption • Package and portion sizes • Serving containers

42. Weight Loss Strategies – Behavior & Attitude • Behavior modification • Positive, matter-of-fact attitude • Become aware of behaviors • Keep record • Change behaviors • Set small, specific goals • Practice • Reward

43. Weight Loss Strategies – Behavior & Attitude • Cognitive skills • Problem solving • Cognitive restructuring • Replace negative thoughts • Personal attitude • Understand personal relationship with food • Sound emotional health • Support groups

44. Weight Loss Strategies – Weight Maintenance • Successful weight loss • Plateau • Appropriate goal at this point • Prevalence of successful weight loss • Difficult to determine • Weight loss • Without formal program • Maintained for at least a year

45. Weight Loss Strategies – Weight Maintenance • Components of successful weight loss • Vigorous exercise regimens • Careful eating patterns • Frequent self-monitoring • Changes in metabolism • Takes more to prevent weight regain than to prevent weight gain

46. Preventing Weight Gain • Preventing weight gain would benefit many people • Strategies are similar to losing weight • Start earlier

47. Public Health Programs • Possibly change environment through public health law • Stretch beyond individual • Social networks • Community institutions • Government policies

48. Public Health Programs

49. Underweight • Affects no more than 5% of U.S. adults • Weight gain is a matter of health • Individual matter • Weight gain may be difficult • Physical conditioning combined with high energy intakes

50. Problems of Underweight • Demand for energy contributes to underweight • Physical activity • Growth and development • Difficult to gain weight • Adaptive thermogenesis • Learn new habits and like new foods • Underweight vs. anorexia nervosa