Weight Management Strategies: Medical and Nutritional Therapy
What is Successful Weight Loss? Common definition: Lose at least 10% of starting weight and keep it off at least one year.
What is the Goal of Obesity Treatment? Specifically, the goal of obesity treatment should be refocused from weight loss alone, which is often aimed at appearance, to weight management, achieving the best weight possible in the context of overall health. –FTC Panel, Commercial Weight Loss Products and Programs What Consumers Stand To Gain and Lose, 1997 http://www.ftc.gov/os/1998/03/weightlo.rpt.htm accessed 3-13-06
Who Should Consider A Weight Management Intervention? Persons with a BMI of >30 Persons with a BMI between 25-29.9 OR a high-risk waist circumference, and two or more risk factors Persons who are ready to change NHLBI Obesity Education Initiative. The Practical Guide Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. NHLBI 00-4084, 2000.
Obesity-Associated Risk Factors: High Absolute Risk Established coronary heart disease Other atherosclerotic diseases Type 2 diabetes Sleep apnea NHLBI Obesity Education Initiative. The Practical Guide Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. NHLBI 00-4084, 2000.
Obesity-Associated Risk Factors: 3 or More = ↑ Risk Hypertension Cigarette smoking High low-density lipoprotein cholesterol Low high-density lipoprotein cholesterol Impaired fasting glucose Family history of early cardiovascular disease Age (male ≥ 45 years, female ≥ 55 years) NHLBI Obesity Education Initiative. The Practical Guide Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. NHLBI 00-4084, 2000.
Other Obesity-Associated Risk Factors Osteoarthritis Gallstones Stress incontinence Gynecological abnormalities NHLBI Obesity Education Initiative. The Practical Guide to Identification, Evaluation, and Treatment of Overweight and Obesity in Adults. NHLBI 00-4084, 2000.
How Much and How Fast? NIH guidelines recommend a weight loss of .5 to 1 pound/week for persons with a BMI of 27-35 and 1-2 pounds a week for those with a BMI>35 kg/m2 Allow 6 months to achieve 10% weight loss After 6 months, focus should shift to weight maintenance for 6 months Following this, weight loss efforts may resume (NIH, 1998)
Weight Loss Goals R.4.0. Individualized goals of weight loss therapy should be to reduce body weight at an optimal rate of 1-2 lbs per week for the first 6 months and to achieve an initial weight loss goal of up to 10% from baseline. These goals are realistic, achievable, and sustainable. Strong, Imperative American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Rates of Weight Loss Vary Men will lose weight faster than women of similar size, due to higher LBM and RMR A heavier person (who has higher energy needs) will lose weight faster than a smaller person on the same caloric regimen
Modest Weight Loss and Health: Diabetes Prevention A 7% weight loss (mean 15 pounds) through diet and exercise in high risk individuals was associated with a 58% reduction of diabetes incidence in the Diabetes Prevention Program DPP Research Group. N Engl J Med. 2002 Feb 7;346(6):393-403. An average 7.7 pound weight loss was associated with a 58% reduction in diabetes incidence in high risk individuals in the Finnish Diabetes Prevention study. FDPS Group. N Engl J Med 344:1343–1350, 2001
Modest Weight Loss and Health: Hypertension Weight loss of as little as 4.5 kg (10 pounds) will improve or prevent hypertension in a large segment of overweight persons. Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) http://www.nhlbi.nih.gov/guidelines/hypertension/jnc7full.pdf Clinically significant long-term reductions in blood pressure and reduced risk for hypertension can be achieved with modest weight loss and increased physical activity. American Dietetic Association Evidence Analysis Library, Hypertension and hyperlipidemia. http://www.adaevidencelibrary.org/
Modest Weight Loss and Health: Hyperlipidemia The ATP-III guidelines recommend a 10% weight loss in overweight persons with hyperlipidemia. http://www.nhlbi.nih.gov/guidelines/cholesterol/atp3full.pdf A weight loss of ≥2.25 kg was associated with a 40-50% reduction in cardiovascular risk factors in the Framingham Offspring Study (BP, triglyceride, TC, FBS, HDL) Karason K et al. Int J Obes Relat Metab Disord 1999;23:948-56.
Modest Weight Loss and Health: Diabetes Calorie restriction and weight loss improves insulin sensitivity and glycemic control in obese patients with Type 2 diabetes. Henry RR et al. J Clin Endocrinol Metab 1985;61:917-25; Kelly DE et al. J Clin Endocrinol MEtab 1993;77:1287-93. A 5% weight loss can decrease FBG, insulin, A1C concentrations and medication requirements. Wing RR et al. Arch Intern Med 1987;147:1749-53.
Setting Weight Management Goals Many severely overweight persons have unrealistic expectations in setting weight loss goals (Blackburn, 1998) Even modest weight loss may produce significant improvements in health For some persons (especially those with BMI of 25-29.9) weight maintenance may be a goal
Evaluation of Body Wt R.1.1 Body mass index (BMI) and waist circumference should be used to classify overweight and obesity, estimate risk for disease, and to identify treatment options. BMI and waist circumference are highly correlated to obesity or fat mass and risk of other diseases (NHLBI report). Fair, Imperative American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Estimation of Energy Needs R.5.0 Estimated energy needs should be based on RMR. If possible, RMR should be measured (e.g., indirect calorimetry). If RMR cannot be measured, then the Mifflin-St. Jeor equation using actual weight is the most accurate for estimating RMR for overweight and obese individuals. Strong, Conditional American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Readiness to Change: A Brief Assessment Has the individual sought weight loss on his/her own initiative? What has led the patient to seek weight loss now? What are the patient’s stress level and mood? Does the individual have an eating disorder?
Readiness to Change: A Brief Assessment Does the individual understand the requirements of treatment and believe that he/she can fulfill them? How much weight does the patient expect to lose?
NIH Recommended Interventions Dietary therapy Physical activity Behavior therapy Pharmacotherapy Bariatric surgery
Comprehensive Wt Mgt Program R.2.0 Weight loss and weight maintenance therapy should be based on a comprehensive weight management program including diet, physical activity, and behavior therapy. The combination therapy is more successful than using any one intervention alone. Strong, Imperative American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Dietary Interventions
Optimal Length of Wt Mgt Therapy R.3.0. Medical Nutrition Therapy for weight loss should last at least 6 months or until weight loss goals are achieved, with implementation of a weight maintenance program after that time. Greater frequency of contacts between the patient and practitioner may lead to more successful weight loss and maintenance. Strong, Imperative American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Goals of Weight Management (NIH) Achievement of healthy body weight (or close to desired BMI) Select a realistic goal—no more than 1 to 1.5 lb/week Prevent loss of LBM, especially from heart and brain Support psychosocial factors
Reduced Calorie Diets R.6.0 An individualized reduced calorie diet is the basis of the dietary component of a comprehensive weight management program. Reducing dietary fat and/or carbohydrates is a practical way to create a caloric deficit of 500 – 1000 kcals below estimated energy needs and should result in a weight loss of 1 – 2 lbs per week. Strong, Imperative American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Balanced Energy-Restricted Diet Is the most widely-prescribed method of weight reduction Should be nutritionally adequate except for energy Energy level varies with individual’s size, sex, and activity, ranging from 800 kcals to 1500 kcals (NIH, 1998)
Balanced Energy-Restricted Diet Should be relatively high in carbohydrate (50-55% of total kcals) CHO sources should be fruits, vegetables, whole grains Include generous protein (15-25% of kcals) for increased satiety and to assure adequate supply Fat < 30% of kcals Increased fiber to improve satiety (NIH, 1998)
Balanced Energy-Restricted Diet Alcohol and high-sugar foods should be limited to limit excess energy Use of non-nutritive sweeteners and fat replacements may improve the palatability of the diet Vitamins and mineral supplements may be needed in programs that provide <1200 kcals for women or 1800 kcals for men (NIH, 1998)
Exchange System Diets Allow flexibility in making food choices while limiting total caloric intake Provides framework for healthy balance of nutrients May be too complex or restrictive for some clients
Nutrition Education R.10.0 Nutrition education should be individualized and included as part of the diet component of a comprehensive weight management program. Short term studies show that nutrition education (e.g. reading nutrition labels, recipe modification, cooking classes) increases knowledge and may lead to improved food choices. Fair, Imperative American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Eating Frequency and Patterns R.7.0 Total caloric intake should be distributed throughout the day, with the consumption of 4 to 5 meals/snacks per day including breakfast. Consumption of greater energy intake during the day may be preferable to evening consumption. Fair, Imperative American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Portion Control R.8.0 Portion control should be included as part of a comprehensive weight management program. Portion control at meals and snacks results in reduced energy intake and weight loss. Fair, Imperative American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Meal Replacements R.9.0 For people who have difficulty with self selection and/or portion control, meal replacements (e.g., liquid meals, meal bars, calorie-controlled packaged meals) may be used as part of the diet component of a comprehensive weight management program. Substituting one or two daily meals or snacks with meal replacements is a successful weight loss and weight maintenance strategy. Strong, Conditional American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Low Glycemic Index Diets R.11a A low glycemic index diet is not recommended for weight loss or weight maintenance as part of a comprehensive weight management program, since it has not been shown to be effective in these areas. Strong, Imperative American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Lowfat Dairy Foods R.11b. In order to meet current nutritional recommendations, incorporate 3-4 servings of low fat dairy foods a day as part of the diet component of a comprehensive weight management program. Research suggests that calcium intake lower than recommended levels is associated with increased body weight. However, the effect of dairy and/or calcium at or above recommended levels on weight management is unclear. Fair, Imperative American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Low Carbohydrate Diets R.11c Having patients focus on reducing carbohydrates rather than reducing calories and/or fat may be a short term strategy for some individuals. Research indicates that focusing on reducing carbohydrate intake (<35% of kcals from carbohydrates) results in reduced energy intake. Consumption of a low-carbohydrate diet is associated with a greater weight and fat loss than traditional reduced calorie diets during the first 6 months, but these differences are not significant after 1 year. Fair, Conditional American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Very Low Calorie Diets (VLCD) Diets providing 200-800 kcals/day Hypocaloric but relatively rich in protein (.8-1.5 g/kg/day) Designed to include adequate vitamins, minerals, electrolytes, and EFAs Completely replace usual meal intake Usually given for 12-16 weeks Usually reserved for those with BMI>30; or 27-30 with risk factors NHLBI, 2000
Protein Sparing Modified Fast (PSMF) Uses real food Contains 1.5 g protein/kg IBW as lean meat, fish and poultry May include low-carbohydrate vegetables Only fat is that present in the protein sources NIH NHLBI The practical guide. Identification, evaluation, and treatment of overweight and obesity in adults. NHLBI, 2000
Commercial VLCD Liquid Diets Contain 33-70 g of protein, 30-45 g CHO, small amount of fat Provides 400-800 kcals Patients lose 20 kg in 12 to 16 weeks NIH NHLBI The practical guide. Identification, evaluation, and treatment of overweight and obesity in adults. NHLBI, 2000
VLCDs Cardiac complications a concern Risks include potassium loss as well as body protein (higher in the less obese) Requires close medical supervision and monitoring of serum electrolytes But VLCDs may be a more effective method of weight loss for some (Anderson et al Am J Clin Nutr 74;579:2001)
Dietary Therapy: NIH Guidelines Very low calorie diets (VLCDs) should not be used routinely for weight loss therapy because they require special monitoring and supplementation LCDs may be just as effective NIH NHLBI The practical guide. Identification, evaluation, and treatment of overweight and obesity in adults. NHLBI, 2000
Behavioral Therapy in Weight Management
Behavioral Therapy: NIH Guidelines Self-monitoring Stress management Stimulus control Problem-solving Contingency management Cognitive restructuring Social support
Behavior Therapy in Wt Mgt R.13.0 A comprehensive weight management program should make maximum use of multiple strategies for behavior therapy (e.g. self monitoring, stress management, stimulus control, problem solving, contingency management, cognitive restructuring, and social support). Behavior therapy in addition to diet and physical activity leads to additional weight loss. Continued behavioral interventions may be necessary to prevent a return to baseline weight. Strong, Imperative American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Self Monitoring Records of place and time of food intake Accompanying thoughts and feelings Helps identify the physical and emotional settings in which eating occurs Provides feedback on progress and puts responsibility on the patient
Problem Solving Process for defining the eating or weight problem Generating possible solutions; evaluating the solutions, choosing the best one Trialing the new behavior, evaluating outcome and generating alternatives
Stimulus Control Modification of The settings or the chain of events that precede eating The kinds of foods consumed The consequences of eating Become mindful of satiety cues Put fork down between bites Pausing during meals
Cognitive Restructuring Teaches patients to identify, challenge, and correct negative thoughts Positive self-talk
Behavior Modification Most effective in mildly obese (20-40% overweight) Patients can maintain losses of 20-25 pounds Longer programs more successful Many patients regain the weight they lost over time NIH NHLBI The practical guide. Identification, evaluation, and treatment of overweight and obesity in adults. NHLBI, 2000
Weight Loss Medications
Pharmacological Therapy NIH Guidelines Should be used only in the context of a program that includes lifestyle changes If lifestyle changes do not promote weight loss after 6 months, drugs should be considered Limited to those with BMI ≥30; or ≥27 with risk factors NIH NHLBI The practical guide. Identification, evaluation, and treatment of overweight and obesity in adults. NHLBI, 2000
Wt Loss Medications R.14.0 FDA-approved weight loss medications may be part of a comprehensive weight management program. Dietitians should collaborate with other members of the health care team regarding the use of FDA-approved weight loss medications for people who meet the NHLBI criteria. Research indicates that pharmacotherapy may enhance weight loss in some overweight and obese adults. Strong, Imperative American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Catecholaminergic Drugs Appetite suppressants Act on the brain, increasing the availability of norepinephrine Schedule II anorexic agents High potential for abuse Include amphetamine, phenmetrazine HCl Not recommended for weight management Schedule III agents Some potential for abuse Include benzphetamine HCl, phendimetrazine tartrate See Table 21-5 Krause 12th edition, p. 551
Catecholaminergic Drugs Schedule IV agents Includes diethypropion HCl, manzindol HCl, phentermine HCl, phentermine resin Low potential for abuse Can raise blood pressure, so prescribed with caution in patients with hypertension NIH NHLBI The practical guide. Identification, evaluation, and treatment of overweight and obesity in adults. NHLBI, 2000
Serotonin Reuptake Inhibitors Includes sibutramine (Meridia) Inhibits the reuptake of serotonin and norepinephrine Initially developed to treat depression Use caution in hypertension, CHD, arrhythmias, CHF NIH NHLBI The practical guide. Identification, evaluation, and treatment of overweight and obesity in adults. NHLBI, 2000
Orlistat (Xenical) Lipase inhibitor Acts directly on the gastrointestinal tract to inhibit fat absorption Associated with reduced LDL-C and increased HDL; improved glycemic control, reduced blood pressure Some concern about fat soluble vitamins Side effects: oily spotting, fecal urgency, flatus with discharge NIH NHLBI The practical guide. Identification, evaluation, and treatment of overweight and obesity in adults. NHLBI, 2000
FDA Approves Reduced Dose of Orlistat for Over the Counter Over the counter dose of orlistat, a lipase inhibitor Half the dose of prescription form (Xenical) The only FDA-approved over the counter wt mgt drug Available summer 2007
Serotoninergic Agents Increase serotonin levels in the brain Fenfluramine hydrochloride and dexfenfluramine HCl (Fen-Phen) were removed from the market in 1997 due to association with heart valve disease and pulmonary hypertension
Pharmacological Obesity Treatments Weight loss of about 1 lb/week can be expected Most weight loss will occur within the first 6 months of therapy Significant weight maintenance as long as the drug treatment is continued Most patients regain weight if medication is stopped
Pharmacological Obesity Treatments Weight-loss medications lead to an additional weight loss of 5 to 22 pounds more than with non-drug obesity treatments Two to 20 kg total loss, usually during first 6 months of treatment When drugs are discontinued, weight regain occurs
Physical Activity and Weight Management
Physical Activity R.12.0 Physical activity should be part of a comprehensive weight management program. Physical activity level should be assessed and individualized long-term goals established to accumulate at least 30 minutes or more of moderate intensity physical activity on most, and preferably, all days of the week, unless medically contraindicated. Physical activity contributes to weight loss, may decrease abdominal fat, and may help with maintenance of weight loss. Strong, Imperative American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Physical Activity: NIH Guidelines Physical activity increases energy expenditure and plays an integral role in weight maintenance Reduces the risk of heart disease more than weight loss alone Reduces body fat, prevents decrease in muscle mass during weight loss All adults: goal of 30 minutes or more of moderate-intensity physical activity on most and preferably all days. NIH NHLBI The practical guide. Identification, evaluation, and treatment of overweight and obesity in adults. NHLBI, 2000
Role of Physical Activity in Weight Management Physical activity usually will not lead to a greater weight loss over diet alone in a 6-month period (NIH, 2000) Physical activity is most helpful in preventing weight regain Physical activity also is beneficial in reducing risk for heart disease and diabetes beyond the effect of weight loss
Role of Physical Activity in Weight Management Exercise helps balance the loss of LBM and reduction in RMR caused by hypocaloric diets A combination of aerobic exercise and resistance training is recommended Even when weight loss does not occur, loss of body fat often does May require 2 months to see loss of weight through exercise
U.S. Dietary Guidelines 2005 Suggest 60 minutes of moderate-vigorous activity on most days of the week to prevent weight gain in adulthood To sustain weight loss in adulthood: at least 60-90 minutes of daily moderate-intensity physical activity Achieve physical fitness by including cardiovascular conditioning, stretching exercises for flexibility, and resistance exercises or calisthenics for muscle strength and endurance. http://www.health.gov/dietaryguidelines/dga2005/recommendations.htm
Role of Physical Activity in Weight Management Other Benefits: —Improved sense of well-being —Relief of boredom —Sense of control —Relief from depression
Bariatric Surgery R.15.0. Dietitians should collaborate with other members of the health care team regarding the appropriateness of bariatric surgery for people who have not achieved weight loss goals with less invasive weight loss methods and who meet the NHLBI criteria. Separate ADA evidence based guidelines are being developed on nutrition care in bariatric surgery. Strong, Imperative American Dietetic Association Evidence Analysis Library Adult Wt Mgt Guidelines, accessed 2/07
Bariatric Surgery: NIH Guidelines Option for well-informed and motivated patients with clinically severe obesity (BMI≥40 or BMI ≥35 with serious co-morbid conditions NIH NHLBI The practical guide. Identification, evaluation, and treatment of overweight and obesity in adults. NHLBI, 2000
Candidates for Bariatric Surgery BMI of 40 or more—about 100 pounds overweight for men and 80 pounds for women BMI between 35 and 39.9 and a serious obesity-related health problem such as type 2 diabetes, heart disease, or severe sleep apnea Willingness to make associated lifestyle changes
Bariatric Surgery Options Restrictive Malabsorptive Combination restrictive/malabsorptive
Restrictive Procedures Adjustable gastric banding (AGB) a hollow band made of silicone rubber is placed around the stomach near its upper end, creating a small pouch and a narrow passage into the rest of the stomach Vertical banded gastroplasty. VBG uses both a band and staples to create a small stomach pouch (not often used today)
Restrictive Surgery: Adjustable Gastric Band
Diet After Surgery After restrictive surgeries, patients can only eat ½ cup to 1 cup of food at a time Foods often must be soft and chewed thoroughly Patients who eat too fast or the wrong kinds of food may have vomiting
Restrictive Procedures: Advantages Don’t interfere with the normal digestive process Easier to perform and generally safer than malabsorptive surgeries AGB often done laparoscopically Can be reversed if necessary
Restrictive Procedures: Disadvantages Generally results in less weight loss Patients generally lose about half of their excess body weight in the first year after restrictive procedures Only 20% keep weight off over 10 years, though there is evidence that AGB is more effective than VBG
Restrictive/Malabsorptive Procedures Roux-en-Y gastric bypass (RGB) is the most common The surgeon creates a small stomach pouch to restrict food intake. Next, a Y-shaped section of the small intestine is attached to the pouch to allow food to bypass the lower stomach, the duodenum and the first portion of the jejunum. This reduces the amount of calories and nutrients the body absorbs.
Restrictive/Malabsorptive: Roux en Y
Restrictive/Malabsorptive Procedures: Advantages Patients lose weight quickly and continue to lose 18-24 months after the procedure With RGB, many patients maintain a weight loss of 60 to 70 percent of their excess weight for 10 years or more
Restrictive/Malabsorptive Procedures: Disadvantages More difficult to perform More likely to result in long-term nutritional deficiencies (calcium, iron) Greater risk of dumping syndrome Increased likelihood of complications including hernia (decreased with laparoscopic procedures)
Weight Management—Children Goals: Weight maintenance or slowing of gains Grow into weight If severely obese, lose no more than 1 lb monthly to reach desired adult weight for height
Weight Management in Children At risk at BMI 85% to 95%ile; obese at 95% Review parents’ history—height, weight, etc. Weight management in children is a family affair
Weight Management in Children Overweight children should try to achieve weight maintenance or slowing of the rate of weight gain, not weight loss Depends on age and degree of overweight Once adult height is achieved, weight loss is necessary to improve health
Summary Even modest weight loss can produce improvements in overall health in persons who are overweight (lipids, BG, insulin, blood pressure) Most persons will need sustained, long-term lifestyle interventions to achieve significant weight loss