Weight Management

Weight Management Chapter 15

Weight Management • CDC (2009-2010 data): • 36% of adults over 20 years in the United States are overweight (BMI 25-29.9) or obese (BMI 30-35) • 69% are overweight, including obesity • Among children ages 2-19 years, approximately 17% are obese and about 15% overweight (CDC, FRAC)

Weight Management • (CDC, 2009-2010 con’t) • Percent of adolescents age 12-19 years who are obese: 18.4% • Percent of children age 6-11 years who are obese: 18.0% • Percent of children age 2-5 years who are obese: 12.1%

Weight Management • Contributed in large part by poor diet, physical inactivity, and genetics • This chapter examines the problem of weight management and seeks a more positive and realistic health model that recognizes personal needs and sound weight goals.

Weight Management • KEY CONCEPTS: • America’s obsession with thinness carries social, physiologic, and biologic costs. • Underlying causes of obesity include a host of various genetic and environmental factors. • Realistic weight management focuses on individual needs and health promotion, including meal pattern planning and regular physical activity • Underlying causes of obesity include a host of various genetic, environmental, and psychological factors

Objectives • Identify problems of obesity and weight control • Describe sound weight management program • Describe the problem of underweight

Obesity and Weight Control • Body Weight and Body Fat • Obesity and Overweight are not the same • Traditional medical definition: • Obesity is a clinical term for excess body fat generally applied to persons who are at least 20% above a desired weight for their height. • Overweight denotes a body weight above a population weight-for –height standard

Obesity and Weight Control • The real health problem = the degree of fatness • I.E, the relative excess amount of fat in the total body composition (Body Mass Index – BMI) • Overweight = BMI of 25 + • Clinical Obesity = BMI of 30+ • Until recently, the important factor of agehad been overlooked • With advancing age, body weight usually increases until approximately age 50 in men and age 70 in women and then declines

Obesity and Weight Control • Body Composition - can be measured with variety of methods: • Provide a better evaluation of overall health relative to weight

Obesity and Weight Control Measurement cont. • Bioelectrical Impedance Analysis – Stand on scale bare foot while a very light electrical current goes through body. Non- invasive, inexpensive • Duel energy x–ray absorptiometry – uses radiation to distinguish bone, muscle, water, and fat density. Expensive. • Air Displacement plethysmography (BodPod)

Obesity and Weight Control • Body fat Calipers- Measures the width of skin folds at specific body sites. These measures are then used in specific formulas to calculate and estimated body fat composition. Non-invasive; inexpensive • Hydrostatic Weighing – Complete submersion of body in water- Exhale as much air as possible and stay under water for a few seconds. Expensive

Obesity and Weight Control Body Composition- • A body content within the range of 21%-25.8% of total body weight is associated with the lowest risk of chronic disease for males 20-70yrs • For women: 32.2%-36.9%%

Obesity and Weight Control • NCSM cont’d • Measuring body fat percentage that is “above average” fitness – “well above average” fitness: • 7%-15.8% (men, ages 20-29 years) • 14.5%-22% (women, 20-29 years)

Measures of Weight Maintenance Goals Standard Height-Weight tables • Healthy Weight Range : a general calculation for determining healthy or “ideal” weight goals: • Males: 106 lbs. for first 5 feet then add or subtract 6 lbs for each inch above or below 5 ft. respectively • A range is then taken by adding or subtracting 10% to account for small and large body frames. • Females: 100 lbs. for first 5 feet then 5 lbs for every inch above or below 5 ft. respectively. Range: as above.

Measures of Weight Maintenance Goals • Healthy Weight Range • Individual Variation: The basic problem with “ideal” body weight is that it varies with different people at different times under different circumstances. • A person’s “ideal” weight depends on many factors: gender, age, body shape, metabolic rate, genetic make-up, and physical activity.

Measures of Weight Maintenance Goals • Healthy Weight Range cont. • Necessity of body fat: some body fat is essential to survival. • Fat is used for insulation, temperature regulation • For survival: males require 3-5% body fat; females 8-12% • Menstruation begins when the female body reaches a certain size, or more precisely, when a young girl’s body fat reaches a critical percentage of body weight (e.g. 20% approx.). This is the amount needed for ovulation and to support a healthy pregnancy.

Obesity and Health • Weight Extremes –Clinically severe or significant obesity is a health hazard in itself and creates other medical problems by placing strain on all body systems • Extreme thinness also poses health problems

Obesity and Health Overweight and Health Problems: • Increases risk for: Diabetes, HTN, heart disease, sleep apnea, gallbladder disease, degenerative joint disease/osteoarthritis, and breast, endometrial, and colon cancers

Causes of Obesity • Basic energy balance – a major cause of obesity in sedentary Americans is lack of physical exercise. • This overall underlying energy imbalance is the ultimate cause for excess weight • A well-defined walking program (without any dietary change) can reduce the amount of body fat in overweight persons

Causes of Obesity • Hormonal Control: Obesity gene- this gene encodes for a hormone released from adipose tissue: under research to determine influence on fat storage set-point. • Researchers named the hormone “leptin” from the Grk. word “leptos” meaning thin or slender

Causes of Obesity • Hormonal Control: • Leptin: signals “enough” when adipose levels rise. A malfunction of this hormone could result in lack of negative feedback control • Ghrelin – an appetite –regulating stimulant secreted from the stomach to increase appetite and promote adiposity

Causes of Obesity • Genetic and Family Factors • Genetic inheritance probably influences a person’s chance of becoming fat more than any other factor. • Family food patterns then provide an environment allowing this genetic trait to present itself. • Also, affects the # and size of fat cells in a body • A person eats to regain or lose whatever amount of fat the body is naturally set or programmed for

Causes of Obesity • Genetic and Family Factors- • This is not to say that a person has not control over his or her body weight • *A genetic influence is a “predisposing factor” not a “determining factor” • The daily life, environment, and habits a person chooses influence the expression of this genetic trait.

Causes of Obesity Environmental factors: • Fast and convenience foods, increase in portion sizes, decrease in food prep time and skills, decreased physical activity, medication, and stressful lifestyles

Causes of Obesity • Role of cortisol: primary stress hormone. Cortisol levels rise in response to physical stressors and with continuous mental and emotional stressors. • Chronically elevated levels of cortisol are associated with loss of muscle mass, increase in blood sugar levels, and increase in body fat – esp. abdominal fat.

Individual Differences • Individual Energy-Balance Levels: • Factors affecting energy-balance include: • BMR, body size, lean body mass, age, gender, and physical activity affect how much energy one burns

Extreme Practices • Extreme practices • Fad diets – fail due to: Scientific inaccuracies and misinformation – Fad diets or supplements are often nutritionally inadequate; and • Fail to provide necessity of changing long term habits •  chronic dieting syndrome

Individual Differences and Extreme Practices Extreme Practices cont. • Extended periods of fasting without excess body reserves: this drastic approach can produce semistarvation effects: acidosis, low BP, electrolyte loss, tissue protein loss, decreased BMR • This is a different pathway than short periods of fasting undertaken for specific short-term reasons • Specific Macronutrient Restriction – avoiding CHO, protein, fat are too restrictive to maintain for extended periods of time. • Don’t confuse with specific therapeutic approaches for specific patients’ needs under healthcare provider supervision (i.e. metabolism, absorption, chronic illness, ect)

Individual Differences and Extreme Practices Extreme Practices cont. • Clothing and Body Wraps – “sauna suits” to treat cellulite tissue • Drugs – various amphetamine compounds (“speed”) no longer used due to health dangers; Dexatrim (similar to amphetamine) -> increased BP, damage to blood vessels in the brain; Fen-phen combination  valvular regurgitation of heart valves, a fatal condition

Individual Differences and Extreme Practices Drugs to treat obesity: • Reduce energy intake by suppressing appetite • Increase energy expenditure by stimulating the BMR • Reduce the availability of nutrients to enter cells • Altering lipogenesis and lipolysis

Individual Differences and Extreme Practices 2 drugs approved by the FDA: Meridia and Xenical • Meridia (sibutramine) increases the heart rate and thus the energy expenditure • Alli/Xenical(orlistat) inhibits dietary fat absorption • Note: weight returns when these meds discontinued

Individual Differences and Extreme Practices • Extreme Practices cont. • Surgery: usually for medical treatment of morbid obesity (BMI>40 or BMI 35-39 with at least one obesity-related disorder) in patients who have not had success with other methods of long-term weight loss • Designed to: 1. reduce the space for food in the stomach  limiting appetite and eating or 2. by inducing malabsorption,  decreasing nutrient availability to the body • Lipectomy: a form of local fat removal (liposuction)

Individual Differences and Extreme Practices

Individual Differences and Extreme Practices • Surgery • Surgical techniques usually are reserved for the medical treatment of clinically sever obesity in patients who have not had success with other methods of long-term weight loss • 2 types performed for weight loss: • Gastric resection • Malabsorption procedures (eg. Gastric bypass)

Gastric bypass surgeries

Sound Weight Management Program • Essential characteristics – No short cuts to successful weight control • Must be a personalized program that focuses on changed food habits; changed exercise behaviors and stress-relaxation habits • Behavior modification – Basic principles: • designed to help people change patterns that contribute to excessive weight • Recondition desirable behavior patterns and plan constructive actions to meet personal health goals

Sound Weight Management Program Behavior Modification cont. • Starts with evaluating undesirable eating behaviors • Cues - What stimulates behavior • Response – What happens during the eating or sedentary behavior after the cue • Consequences – What happens after the response to the eating or sedentary behavior that serves to reinforce it

Sound Weight Management Program Behavior Modification- Basic strategies and actions Directed toward: control of eating behavior; promotion of physical activity; emotional, social, and psychological health Defining problem behavior specifically. Also, define the desired behavior outcome

Sound Weight Management Program Behavior Modification cont. • Recording and analyzing baseline behavior – record eating and exercise behavior. What type of habit patterns emerge? • Planning behavior-management strategy – setting up controls for external environment involving the situational forces r/t each of the behavior areas involved

Dietary Principles • Recommended for lasting results: • Realistic goals in terms of wt. loss and rate of loss averaging ½ to 1 lb. / week (no more than 2 lbs/wk for obese people) • Energy (kilocalories) reduced according to need – must have sufficient energy intake in relation to individual output  gradual wt. loss

Dietary Principles • Nutritional adequacy – should have appropriate balance based on a wide varied of food sources; may need vit/min supplementation if consuming less food • Cultural appeal – food pattern similar to the individuals cultural eating pattern • Energy (kilocalorie) readjustment to maintain weight after achieved desired result

Basic Energy–Balance Components • Two components: • Energy intake: in the form of food • Energy output: in the form of metabolic work and physical activity • Energy Input: Food behaviors - energy value of food intake must be reduced • The usual amount of food served and eaten should be noted • Then, smaller portions should be used • Reduce overall use of fat, sugar, and salt • Choose from a variety of foods

Basic Energy–Balance Components • Energy output: Exercise behaviors – must be increased • Start with simple walking for 30 min / day • Then add some form of aerobic exercise + resistance exercise

Principles of recommended food plans • Energy balance – When energy expenditure is greater than energy intake  wt. Loss. • E.g. – 1 lb. of fat = 3500 kcal; an energy deficit of 500 kcal/day  wt. Loss of approx. 1 lb. / week • All persons pursuing wt. loss should determine their total energy needs as a basis for diet planning. A prefabricated calorie amount/day is not appropriate (eg. Allowing only 1400 cal/day) – it doesn’t take into account an individuals needs • Ideal scenario: 250 kcal deficit by reducing calorie intake + 250 kcal increase in energy expenditure

Principles of recommended food plans Nutrient balance • Carbohydrate 45 – 65 % of total kcals • Protein 10 – 35 % • Fat 10 – 25 %

Weight Management