1. 5
Weight Management

2. Weight Management
Obesity is a body mass index (BMI) of 30 or higher, when excess body fat can lead to serious health problems
An estimated 35% of the adult population in industrialized nations is obese
The average weight of American adults has increased by 25 pounds or more since 1965
The prevalence of obesity is higher in African Americans and Hispanic Americans

3. Overweight and Obese in the US
Figure 5.1. Percentage of the adult population (20 years) that is normal weight (BMI 25), overweight (BMI ) and or obese (BMI >30) in the United States.

4. Weight Management (cont’d.)
Excessive body weight combined with physical inactivity is the second leading cause of preventable death in the United States
Obesity and unhealthy lifestyle habits are the most critical public health problems we face in the 21st century

5. Overweight versus Obesity
Overweight and obese are not the same thing
Obesity results in:
Decrease in life expectancy
Decrease in quality of life
Increase in illness and disability

6. Overweight versus Obesity (cont’d.)
A primary objective to achieve overall physical fitness and enhanced quality of life is to attain recommended body composition
Being underweight is also a problem that can lead to many medical disorders and death – about 14% of people in the US are underweight

7. Tolerable Weight
When people set their own target weight, they should be realistic
“Ideal” body shapes illustrated in popular magazines are achieved mainly through airbrushing and medical reconstruction
Failure to attain a “perfect body” may lead to eating disorders in some individuals

8. The Weight Loss Dilemma
Frequent fluctuations in weight (yo-yo dieting) markedly increase the risk for dying from cardiovascular disease
Quick-fix diets should be replaced by a slow but permanent weight-loss program

9. The Weight Loss Dilemma (cont’d.)
Diet without exercise
Only ~10% of people who begin program are able to lose desired weight
Only ~5% are able to keep it off
Traditional diets fail because few of them incorporate permanent behavioral changes

10. Self-Reported versus Actual Caloric Intake and Exercise
Figure 5.4. Self-reported versus actual daily caloric intake and exercise in obese individuals attempting to lose weight.

11. Diet Crazes
Fad diets deceive people and claim that dieters will lose weight by following all instructions
With diets that are very low in calories, a lot of the weight loss is water and protein, not fat
Dropout rates are high because of difficulty adhering to limited dietary plans
Popular diets: DASH, Volumetrics, Best Life, Weight Watchers, Ornish, Zone, Atkins, South Beach, Glycemic Index Diet, Biggest Loser, Mediterranean

12. Crash Diets Less than 800 calories/day
Glycogen storage is depleted in a few days
Half the weight loss is lean (protein) tissue, including heart muscle
Increases risk of heart attacks or fatal cardiac arrhythmias
Sodium depletion may cause a dangerous drop in blood pressure

13. Low-Carb Diets Low-carbohydrate/high-protein (LCHP) diets
Eat all the protein foods you want
Limited fruits and vegetables
High in fat
Low glycemic index; slows insulin response
Rapid weight loss due to loss of lean tissue and body water; effectiveness dwindles over time
Increases the risk for heart disease, cancer, and kidney or bone damage

14. Key Terms
Glycogen
Manner in which carbohydrates (glucose molecules) are stored in the human body, predominantly in the liver and muscles.
Glycemic index
Used to rate the plasma glucose response of carbohydrate-containing foods with the response produced by the same amount of a standard carbohydrate, usually glucose or white bread

15. Effects of High- and Low-Glycemic Intake on Blood Glucose Levels
Figure 5.5. Effects of high- and low-glycemic intake on blood glucose levels.

16. Eating Disorders
Eating disorders are medical illnesses characterized by intense fear of becoming fat – thought to stem from environmental pressures
Anorexia nervosa: self-imposed starvation Bulimia nervosa: pattern of binge eating and purging
Binge-eating disorder: uncontrollable episodes of eating excessive amounts of food within a relatively short time
Emotional eating: consumption of large quantities of food to suppress negative emotions

17. Eating Disorders (cont’d.)
Most prevalent in women 25 to 50
Often a coping mechanism to avoid dealing with family and social problems
Clinical depression
Obsessive-compulsive behavior
Chemical dependency
Victims of sexual molestation

18. Eating Disorders (cont’d.)
Eating disorders develop in stages:
Start with weight loss diet
Dieting becomes extreme
Often combined with exhaustive exercise and overuse of laxatives and diuretics
Becomes the primary focus of attention

19. Anorexia Nervosa Fear of weight gain is greater than fear of death
Distorted image of body
Preoccupation with food/meal planning
Diagnostic criteria:
Refusal to maintain body weight
Intense fear of gaining weight or becoming fat
Altered perception of body weight, size, or shape
Amenorrhea
Treatment requires professional help

20. Bulimia Nervosa More prevalent than anorexia nervosa Binge-purge cycle
Mostly well-educated, near recommended weight, emotionally insecure, lacking self-esteem
Binge-purge cycle
Anticipation of cycle
Urgency to begin binging
Eating large and uncontrollable amounts
Short period of satisfaction
Feelings of guilt, shame, and fear
Purging

21. Bulimia Nervosa (cont’d.)
Diagnostic criteria:
Recurrent episodes of binge eating
Self-induced vomiting; misuse of laxatives, diuretics, other medications, or enemas; fasting; or excessive exercise
Binging and compensatory behaviors both occur at least twice a week for three months
Undue importance of body shape and weight

22. Binge-Eating Disorder
Causes are unknown; triggered by depression, anger, sadness, boredom
Do not purge; may be overweight or obese
Diagnostic criteria:
Eating an unusually large amount of food
Eating until uncomfortably full
Eating out of control; faster than usual
Eating alone because of embarrassment
Feeling disgusted, depressed, or guilty

23. Emotional Eating
Emotional eating involves consumption of large quantities of “comfort” and junk food to suppress negative emotions
Foods such as chocolate cause the body to release mood-elevating opiates, helping to offset negative emotions

24. Dealing with Emotional Eating
Differentiate between emotional and physical hunger
Avoid unhealthy foods
Keep healthy snacks handy
Use countering techniques
Keep a “trigger log”
Work it out with exercise instead of food

25. Treatment
Treatment for eating disorders is available through school counseling or health centers and local hospitals
Many communities have support groups led by professional personnel

26. Physiology of Weight Loss
Three assumptions:
Balancing food intake against output allows a person to achieve recommended weight
All fat people simply eat too much
The human body doesn’t care how much (or little) fat it stores
Obesity involves a combination of genetics, behavior, and lifestyle factors

27. Energy-Balancing Equation
As long as caloric input equals caloric output, a person will not gain or lose weight
If caloric intake exceeds output, the person gains weight
When output exceeds input, the person loses weight
Estimated energy requirement (EER): average energy (caloric) intake that is predicted to maintain energy balance for a specific person

28. Energy-Balancing Equation (cont’d.)
Three components of total daily energy requirement:
Resting metabolic rate (energy required to maintain vital body processes in resting state)
Thermic effect of food
Physical activity

29. Components of Total Daily Energy Requirement
Figure 5.6. Components of total daily energy requirement

30. Energy-Balancing Equation (cont’d.)
One pound of fat = 3,500 calories
Two people with similar measured caloric intake and output seldom lose weight at the same rate
Several theories might explain these individual variations

31. Setpoint Theory
A weight-regulating mechanism (WRM) in the human body has a setpoint for controlling both appetite and the amount of fat stored
Every person has his or her own body fat percentage that the body attempts to maintain
Under calorie reduction, the body may make metabolic adjustments to maintain its setpoint
The basal metabolic rate (BMR) may drop dramatically under a consistent negative caloric balance, and weight loss may plateau

32. Key Terms Weight-regulating mechanism (WRM) Setpoint
The hypothalamus of the brain controls how much the body should weigh
Setpoint
Weight control theory that the body has an established weight and strongly attempts to maintain that weight

33. Key Terms Basal metabolic rate (BMR) Very-low-calorie diet
The lowest level of oxygen consumption necessary to sustain life
Very-low-calorie diet
Diet that allows an energy intake of only 800 calories or less per day

34. Recommendation
Daily caloric intake of about 1,500 calories, distributed properly over the basic food groups
Keep track of nutrients and calories consumed
Combine a sensible calorie-restricted diet with an increase in daily physical activity

35. Lowering the Setpoint
Factors that affect the setpoint directly by lowering the fat thermostat:
Exercise
Diet high in complex carbohydrates
Nicotine
Amphetamines
The last two are more destructive than the extra fat weight

36. Diet and Metabolism
When dieters lose weight by dietary restrictions alone, they lose lean body mass – weakens the organs and muscles and slows metabolism
When diet is combined with exercise, almost 100% of weight loss is fat, and lean tissue actually may increase

37. Diet and Metabolism (cont’d.)
Being sedentary is the main cause of lower metabolic rate, not aging
Basal metabolism is related to lean body weight
Severe caloric restrictions always prompts the loss of lean tissue

38. Diet and Fat Loss
Figure 5.7. Outcomes of three forms of diet on fat loss.

39. Regulation of Appetite
Ghrelin, produced primarily in the stomach, stimulates appetite
Leptin, produced by fat cells, lets the brain know when you are full
Lack of physical activity leads to leptin resistance, leading to excessive eating
Sleep deprivation elevates ghrelin levels and decreases leptin levels, potentially leading to weight gain or keeping you from losing weight

40. Monitoring Body Weight
A critical component of weight management is to regularly monitor your body weight
Easier to make short-term changes to lose one or two pounds of weight than to make drastic long term changes to lose 10 or more pounds gained over several months or years

41. Exercise and Weight Management
Physical inactivity may be the primary cause leading to excessive weight and obesity
How much exercise do we need?
For health benefits
30 minutes five days per week
To prevent weight gain
60 minutes daily
To maintain substantial weight loss
90 minutes daily

42. Exercise and Weight Management (cont’d.)
A combination of aerobic and strength-training exercises works best for losing weight
Aerobic exercise is best to offset the setpoint
Strength training is critical in helping maintain and increase lean body mass
Exercise helps increase muscle tissue, connective tissue, blood volume, glycogen, enzymes and other structures within the cell
FTO gene: only partially responsible for weight; lifestyle choices more important

43. The Role of Exercise Intensity and Duration
Compared with vigorous intensity, a greater proportion of calories burned during light- intensity exercise are derived from fat
Overall, you can burn twice as many calories during vigorous-intensity exercise and, subsequently, more fat as well

44. Energy Expenditure at Different Intensity Levels
Table 5.2. Comparison of Approximate Energy Expenditure Between Minutes of Exercise at Three Intensity Levels

45. Overweight and Fit Debate
Can a person be overweight and fit?
Studies show higher aerobic fitness = lower mortality rate regardless of overweight or not
However, debate rages based on the definition of fit
Most fitness professionals do not agree that a person can be fit and fat
There are more than 50 medical conditions related to excess weight

46. Healthy Weight Gain
For “skinny” people, the only healthy way to gain weight is through exercise (strength- training) and a slight increase in caloric intake
Higher caloric intake must be accompanied by a strength-training program; otherwise, the increase in body weight will be in the form of fat, not muscle tissue

47. Weight Loss Myths Spot reducing Cellulite
Fallacious theory proposing that exercising a specific body part will result in significant fat reduction in that area
Cellulite
These deposits are nothing but enlarged fat cells from excessive accumulation of body fat
Other quick-weight-loss myths:
Rubberized sweat suits, steam baths, and mechanical vibrators

48. Losing Weight the Sound and Sensible Way
Don’t try to do too much too fast
Benefits of exercise for weight control
Sensible caloric reduction
Exception: those already eating too few calories
Make wise food choices
Think long-term benefits instead of instant gratification
Estimate daily energy requirement (EER) based on age, total body weight, and gender

49. Estimated Energy Requirement (EER)
Table 5.3. Estimated Energy Requirement (EER) Based on Age, Body Weight, and Height

50. Losing Weight the Sound and Sensible Way (cont’d.)
Determine average of calories burned daily from exercise, total minutes exercised weekly, and daily average exercise time
Obtain the daily energy requirement, with exercise, needed to maintain body weight
Target caloric intake to lose weight: EER – current weight x 5
This final caloric intake to lose weight should not be below 1,500 daily calories for most people

51. Losing Weight the Sound and Sensible Way (cont’d.)
Successful diets: about 24% calories from fat, 56% from carbohydrates, and 20% from protein
Breakfast is a critical meal while on a weight- loss program
Consuming most of your daily calories in one meal may cause more calories to be stored as fat
Consuming most calories earlier in the day helps lose weight and manage atherosclerosis

52. Monitoring Your Diet with Daily Food Logs
People who monitor daily caloric intake are more successful at weight loss than those who don’t
To lose weight, use the diet plan that most closely approximates your target caloric intake
Pay particular attention to food serving sizes, and read food labels carefully

53. Low-Fat Entrees
Use commercially prepared low-fat frozen entrees for lunch and dinner meals
Look for entrees that provide about 300 calories and no more than six grams of fat
Or prepare a similar meal using 3 ounces (cooked) lean protein with additional vegetables, that will provide 300 calories and 6 grams of fat

54. Protein Intake
Minimize loss of lean body mass and hunger pains with more protein
g of protein per kg of body weight per day
Look for fat-free or low-fat protein sources
Greek yogurt, eggs, lean meat, tofu, quinoa, beans

55. Effect of Food Choices on Long-Term Weight Gain
Regardless of other lifestyle habits, individuals who consume unhealthy foods gain more weight, and those who make healthy food choices gain less weight
Weight gain is strongly associated with the consumption of potato chips, potatoes, sugar- sweetened beverages, and red meats

56. Behavior Modification and Adherence
If weight management is to become a priority, people must transform their behavior
Surround yourself with people who have the same goals as you do

57. The Simple Truth Weight management is a lifetime commitment
When taking part in a weight (fat) reduction program, people also have to decrease caloric intake moderately, be physically active, and modify unhealthy eating behaviors
Three common reasons for relapse
Stress-related factors
Social reasons
Self-enticing behaviors
Those who persist will reap the rewards

58. Assess Yourself
Are you satisfied with your current body composition and quality of life? If not, are you willing to do something about it?
Do you understand the following concepts?
The health consequences of obesity
Fad diets, myths, and fallacies about weight
Eating disorders
Physiology of weight loss & setpoint theory
Behavior modification techniques that support adherence to healthy habits