Physical Activity, Drugs, Surgery, and Other Treatment for Overweight and Obesity

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Chapter 6
Physical Activity, Drugs, Surgery, and Other Treatment for Overweight and Obesity

Lack of activity destroys the good condition of every human being, while movement and methodical physical exercise save it and preserve it.

—Plato

One credible hypothesis about the source of the epidemic of overweight and obesity in the United States is the progressive decrease in physical activity expended in daily life—for work, transportation, and household chores. Some researchers contend that the average caloric intake of Americans has not substantially increased; instead by reducing daily physical activity, the caloric imbalance between calories consumed and expended has shifted to favor weight gain. While no data conclusively prove this hypothesis, evidence does support it.

Among the recent studies that support the premise that Americans' sedentary lifestyles have precipitated the obesity epidemic is research that examined the diets of an Amish community in Ontario, Canada. In "Physical Activity in an Old Order Amish Community" (Medicine & Science in Sports & Exercise, vol. 36, no. 1, January 2004), researchers described the "Amish paradox—" that despite a diet that is high in fat, calories, and refined sugar, the Amish community had a scant 4% obesity rate, compared to 31% in the general U.S. population. Exercise science researcher David Bassett and his colleagues chose this particular Amish population because it has rejected technological advances such as automobiles and electricity, and its physically demanding lifestyle is in many ways comparable to the way Americans lived 150 years ago. (Other Amish communities that have assumed occupations less physically active than farming have obesity rates that are similar to those found in the general U.S. population.) The researchers analyzed the daily routines of about 100 Amish people and found that men averaged about 18,000 steps per day and women about 14,000, compared to the recommended 10,000 steps per day that most Americans struggle to achieve. The Amish men performed about ten hours per week of vigorous exercise and women spent about three-and-a-half hours engaged in heavy lifting, shoveling, digging, shoeing horses, or tossing straw bales. Men devoted an additional forty-three hours per week and women an average of thirty-nine hours to such moderate physical activities as gardening, performing farm-related chores, or doing laundry.

PHYSICAL ACTIVITY

In sharp contrast to the Amish farmers, many Americans in the early twenty-first century are not physically active. The Centers for Disease Control defines the minimum recommended physical activity level for adults as "moderate-intensity activity at least thirty minutes per day, five or more days per week, or vigorous-intensity activity at least twenty minutes per day, three or more days per week—in 2003 about 54% of adults age eighteen or older did not engage in the minimum recommended physical activity. The percent of men and women that are physically inactive during leisure time increases with age and income. According to the CDC in Health, United States, 2005, more than half of adults age sixty-five and older said they were physically inactive during leisure time compared with about one-third of adults aged eighteen to forty-four. Women were more physically inactive than men of the same age across all age groups. This pattern begins early—among high school students at every grade level, significantly fewer female students reported engaging in moderate or vigorous physical activity.

The 2004 National Health Interview Survey data revealed that even fewer adults age eighteen and over engaged in regular leisure-time physical activity than did in 2003. (See Figure 6.1.) Figure 6.2 shows that non-Hispanic white adults were more likely than Hispanic adults and non-Hispanic black adults to participate in regular leisure-time physical activity. In 2004 poor and near-poor adults were less likely than those who were not poor to obtain leisure-time physical activity and were more likely to be inactive. (See Figure 6.3.)

Physical Activity and Weight Loss

Increasing physical activity and exercise is an important element of regimens intended to produce weight loss, even though the addition of exercise to a diet program generally does not produce substantially greater weight loss—the majority of weight lost is attributable to decreased caloric intake. By favorably affecting blood lipids, increased and sustained physical activity does offer many direct and indirect health benefits including reducing risks for cardiovascular heart disease and Type 2 diabetes beyond the risk reduction possible through diet alone. Physical activity lowers LDL cholesterol and triglycerides, increases HDL cholesterol, reduces abdominal fat as measured by waist circumference, and may protect against a decrease in muscle mass during weight loss.

Health professionals deem physical activity important for people who are overweight because it leads to increased expenditure of energy and may serve to inhibit food consumption by reducing appetite. Although it generates only very modest weight loss—a 2% to 3% decrease in body weight or body mass index (BMI)—physical activity is helpful for preventing regain of lost weight.

Like those who have been inactive or sedentary, overweight people are advised to initiate physical activity slowly and gradually. Walking and swimming at a slow pace are ideal activities because they are enjoyable, easy to schedule, and less likely to produce injuries than many competitive sports. Table 6.1 is an example of a walking program that progressively increases physical activity. Further, because amounts of activity and the resulting health benefits are functions of the duration, intensity, and frequency, the same amounts of activity may be obtained in longer sessions of moderately intense activity such as brisk walking than in shorter sessions of more strenuous activities such as running. Table 6.2 shows how a moderate amount of activity—physical activity that uses about 150 calories of energy per day for a total of about 1,000 calories per week—can be obtained in a variety of ways. Table 6.2 also indicates how performing common household chores, and even such self-care activities as using a wheelchair, may be used to fulfill requirements for moderate amounts of physical activity. Changing routines to include walking up stairs rather than taking an elevator or parking farther than usual from work, school, or shopping are ways to increase physical activity incrementally. Even reducing sedentary time, such as hours spent in front of the television, video game system, or computer can serve to increase energy expenditure.

Table 6.2 also shows the relationship between the intensity and duration of physical activities by comparing the amount of time a 154-pound adult must spend performing each activity to expend 150 calories. It is interesting to note that just five additional minutes of walking at a moderate pace expends the same number of calories as walking at a brisk pace.

A study conducted by John Jakicic and his colleagues at the University of Pittsburgh Physical Activity and

TABLE 6.1
A sample walking program
Warm up Exercising Cool down Total time
source: "A Sample Walking Program," in The Practical Guide: Identification, Evaluation, and Treatment of Overweight and Obesity in Adults, National Institutes of Health, National Heart, Lung, and Blood Institute, North American Association for the Study of Obesity, October 2000, http://www.nhlbi.nih.gov/guidelines/obesity/practgde.htm (accessed January 12, 2006)
Week 1
   Session AWalk 5 min.Then walk briskly 5 min.Then walk more slowly 5 min.15 min.
   Session BRepeat above pattern
   Session CRepeat above pattern
Continue with at least three exercise sessions during each week of the program
Week 2Walk 5 min.Walk briskly 7 min.Walk 5 min.17 min.
Week 3Walk 5 min.Walk briskly 9 min.Walk 5 min.19 min.
Week 4Walk 5 min.Walk briskly 11 min.Walk 5 min.21 min.
Week 5Walk 5 min.Walk briskly 13 min.Walk 5 min.23 min.
Week 6Walk 5 min.Walk briskly 15 min.Walk 5 min.25 min.
Week 7Walk 5 min.Walk briskly 18 min.Walk 5 min.28 min.
Week 8Walk 5 min.Walk briskly 20 min.Walk 5 min.30 min.
Week 9Walk 5 min.Walk briskly 23 min.Walk 5 min.33 min.
Week 10Walk 5 min.Walk briskly 26 min.Walk 5 min.36 min.
Week 11Walk 5 min.Walk briskly 28 min.Walk 5 min.38 min.
Week 12Walk 5 min.Walk briskly 30 min.Walk 5 min.40 min.
Week 13 on: Gradually increase your brisk walking time to 30 to 60 minutes, three or four times a week. Remember that your goal is to get the benefits you are seeking and enjoy your activity

Weight Management Center, "Effect of Exercise Duration and Intensity on Weight Loss in Overweight, Sedentary Women: A Randomized Trial" (Journal of the American Medical Association, vol. 290, no. 10, September 10, 2003), confirmed the weight-loss benefits of even moderate exercise. The study divided 201 women aged twenty-one to forty-five into four groups. Two groups of women expended 1,000 calories per week walking at a moderate pace for forty minutes a day. The other two groups expended 2,000 calories per week; one group walked at a moderate pace for sixty minutes a day and the other at a vigorous pace for forty-five minutes a day. All of the study participants reduced their calorie consumption to between 1,200 and 1,500 calories per day. The investigators found no differences based on different exercise durations and intensities—one group of women lost almost as much weight—about thirteen to twenty pounds over twelve months—from walking at a moderate pace as another group did from walking at a brisk pace.

Another study, supported by the National Heart, Lung and Blood Institute and conducted by Cris Slentz, and his colleagues at Duke University Medical Center found a dose-relationship between exercise and weight loss—increasing amounts of exercise yielded greater benefits ("Effects of the Amount of Exercise on Body Weight, Body Composition, and Measures of Central

Obesity: STRRIDE-A Randomized Controlled Study," Archives of Internal Medicine, vol. 164, no. 1, January 12, 2004). The study randomly assigned 182 sedentary, overweight adults aged forty to sixty-five to one of four groups: a control group with no exercise; supervised low-dose/moderate-intensity exercise equivalent to walking twelve miles per week; low-dose/vigorous-intensity exercise equivalent to jogging twelve miles per week; or high-dose/vigorous-intensity exercise equivalent to jogging twenty miles per week. The subjects were advised to maintain their weight and not to change their diets. The researchers followed the subjects for eight months and then measured weight, body-fat, waist circumference and lean muscle mass.

TABLE 6.2
Examples of moderate amounts of physical activitya
Common chores Sporting activities
aA moderate amount of physical activity is roughly equivalent to physical activity that uses approximately 150 calories of energy per day, or 1,000 calories per week.
bSome activities can be performed at various intensities; the suggested durations correspond to expected intensity of effort.
source: "Appendix H. Examples of Moderate Amounts of Physical Activity," in The Practical Guide: Identification, Evaluation, and Treatment of Overweight and Obesity in Adults, National Institutes of Health, National Heart, Lung, and Blood Institute, North American Association for the Study of Obesity, October 2000, http://www.nhlbi.nih.gov/guidelines/obesity/practgde.htm (accessed January 12, 2006)
Washing and waxing a car for 45-60 minutesPlaying volleyball for 45-60 minutes
Washing windows or floors for 45-60 minutesPlaying touch football for 45 minutes
Gardening for 30-45 minutesWalking 1 3/4 miles in 35 minutes (20 min/mile)
Wheeling self in wheelchair for 30-40 minutesBasketball (shooting baskets) for 30 minutes
Pushing a stroller 1 1/2 miles in 30 minutesBicycling 5 miles in 30 minutes
Raking leaves for 30 minutesDancing fast (social) for 30 minutes
Walking 2 miles in 30 minutes (15 min/mile)Water aerobics for 30 minutes
Shoveling snow for 15 minutesSwimming laps for 20 minutes
Stairwalking for 15 minutesBasketball (playing a game) for 15-20 minutes
Jumping rope for 15 minutes
Running 1 1/2 miles in 15 minutes (15 min/mile)

Weight change was 3.5% loss in the high-dose/vigorous-intensity group, about 1% loss in the two low-dose exercise groups, compared with a 1.1% gain in the control group. Increases in lean body mass were 1.4% in the two vigorous intensity groups and 0.7% in the low-intensity group. Body fat mass increased by 0.5% in the control group and decreased by 2.0% in the low-dose/moderate-intensity group, by 2.6% in the low-dose/vigorous-intensity group, and by 4.9% in the high-dose/vigorous-intensity group. Waist circumference increased by 0.8% in the control group and decreased by 1.6% in the low-dose/moderate-intensity group, by 1.4% in the low-dose/vigorous-intensity group, and by 3.4% in the high-dose/vigorous-intensity group. The three exercise groups also had significantly decreased waist and hip circumference measurements compared with controls.

Discussing their results, the researchers offered that "From the perspective of prevention, it appears that the thirty minutes per day will keep most people from gaining the additional weight associated with inactivity. Given the increase in obesity in the U.S., it would seem likely that many in our society may have fallen below this minimal level of physical activity required to maintain body weight."

MEDICATION

Pharmacotherapy for weight loss involves the use of prescription drugs as one of several strategies including diet, physical activity, behavioral therapy, counseling, and participation in group-support programs that in combination can work to effect weight loss. Adding weight-loss medications to a comprehensive treatment program consisting of diet, physical activity, and counseling increases weight loss by five to twenty pounds during the first six months of treatment. The decision to add prescription drugs to a treatment program usually considers the individual's BMI, other medical problems, or coexisting risk factors. Table 6.3 shows the therapies appropriate for people with differing BMIs and takes into account the presence of comorbidities such as diabetes, severe obstructive sleep apnea, or heart disease.

Most drugs used for weight loss are appetite suppressants (anorexiants) that act on neurotransmitters (chemical substances that convey impulses from one nerve cell to another) in the brain. Anorexiant drugs vary depending on which neurotransmitters they affect—some have an effect on catecholamines such as dopamine and norepi-nephrine; others affect serotonin; and a third class of drugs acts on more than one neurotransmitter. The drugs act by increasing the secretion of dopamine, norepinephrine, or serotonin, by inhibiting reuptake of neurotransmitters, or by a combination of both mechanisms. For example, sibutramine (Meridia) inhibits the reuptake of norepinephrine and serotonin.

Another class of weight-loss drugs blocks absorption of fat. Orlistat, approved by the U.S. Food and Drug Administration (FDA) in 1999 as Xenical, decreases fat

TABLE 6.3
A guide to selecting treatment
Treatment BMI category
25-26.9 27-29.9 30-34.9 35-39.9 ≥40
The + represents the use of indicated treatment regardless of comorbidities.
source: "Table 3. A Guide to Selecting Treatment," in The Practical Guide: Identification, Evaluation, and Treatment of Overweight and Obesity in Adults, National Institutes of Health, National Heart, Lung, and Blood Institute, North American Association for the Study of Obesity, October 2000, http://www.nhlbi.nih.gov/guidelines/obesity/practgde.htm (accessed January 12, 2006)
Diet, physical activity, and behavior therapyWith comorbiditiesWith comorbidities+++
PharmacotherapyWith comorbidities+++
SurgeryWith comorbidities
  • Prevention of weight gain with lifestyle therapy is indicated in any patient with a BMI ≥25 kg/m2, even without comorbidities, while weight loss is not necessarily recommended for those with a BMI of 25-29.9 kg/m2 or a high waist circumference, unless they have two or more comorbidities.
  • Combined therapy with a low-calorie diet (LCD), increased physical activity, and behavior therapy provide the most successful intervention for weight loss and weight maintenance.
  • Consider pharmacotherapy only if a patient has not lost 1 pound per week after 6 months of combined lifestyle therapy.

absorption by the gut by about one-third. Because it also inhibits absorption of water and vitamins, some users suffer from cramping and diarrhea. The determination of which type of drug to prescribe is based on individual patient characteristics—sibutramine works best for people who are preoccupied with food and feel constantly hungry, while orlistat may be effective for those who are unwilling to reduce fat from their diets. Neither drug has demonstrated remarkable effectiveness. One study found that during the course of a year, orlistat increased weight loss by an average of 2% to 3% beyond that weight loss attributable to dieting alone. Table 6.4 displays the recommended doses of sibutramine and orlistat, potential adverse effects, and compares their mechanisms of action.

Several weight-loss drugs that appeared effective and were popular among consumers have been withdrawn from the U.S. market because of the number and severity of adverse side effects associated with their use. During the 1990s a combination of two drugs—phentermine and fenfluramine, commonly known as "phen-fen" was prescribed for long-term use (more than three months); however, rare but unacceptable side effects, including serious damage to the heart valves, prompted the withdrawal of fenfluramine and a similar drug, dexfenfluramine, in September 1997. Phentermine, one half of the "phen-fen" combination, is still approved for short-term use.

The Practical Guide to the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults (October 2000), prepared by the National, Heart, Lung, and Blood Institute of the National Institutes of Health (NIH), reminds health-care practitioners that not every patient responds to drug therapy, and reiterates that only patients at increased health risk because of their weight should be given weight-loss medications. Further, it emphasizes that drugs should only be used as part of a comprehensive treatment program and that people taking drugs must be closely monitored for side effects.

Research Focuses on New Weight-Loss Drugs

In "Experimental Drugs Take Aim at Obesity" (Journal of the American Medical Association, vol. 289, no. 14, April 9, 2003), Brian Vastag lamented the fact that five years after the FDA ban of fenfluramine, just three prescription weight-loss drugs remained available in the United States. Only two of the drugs, orlistat and sibutramine, were approved for long-term use, and evidence indicates that many users experience "rebound" weight gain when the use of either of these drugs is discontinued. Although these two FDA-approved weight-loss drugs for long-term use were the only drugs available by prescription to consumers at the close of 2005, more than seventy new drugs were in various stages of development.

Researchers have identified ghrelin, a hormone that may be involved in establishing hunger and satiety set points. When the stomach is empty it releases ghrelin, which in turn triggers hunger signals in the brain. Blood levels of ghrelin peak before meals and decrease after eating. Since ghrelin appears to increase appetite and slow metabolism, an excess of it may sabotage long-term weight-loss efforts. Small studies show that ghrelin levels are higher in obese patients who have recently lost weight compared with obese patients at a steady weight. During 2005 pharmaceutical companies were seeking to create drugs that safely and effectively block ghrelin's effects. An analogous approach seeks to boost levels of a peptide known as PYY that produces the opposite effects of ghrelin. After eating, the stomach and digestive tract release PYY, conveying the satiety signal to the brain. In one small study, subjects given the hormone ate a third less food from a buffet.

While drugs to inhibit ghrelin and increase PYY have not yet been formulated, during 2004 and 2005, a new appetite-suppressing drug called Axokine was undergoing clinical trials. Axokine is a modified form of a naturally occurring protein, called ciliary neurotrophic factor, and acts by signaling the satiety center of the brain to decrease food intake. In March 2003 preliminary data from about 2,000 subjects taking Axokine showed that subjects treated with Axokine lost more weight than those who received a placebo (an inactive substance used as a control in an experiment), and suggested that it may not produce the same rebound effect seen with sibutramine.

TABLE 6.4
Weight loss drugs*
Drug Dose Action Adverse effects
*Ephedrine plus caffeine, and fluoxetine have also been tested for weight loss but are not approved for use in the treatment of obesity. Mazindol, diethylpropion, phentermine, benzphetanine, and phendimetrazine are approved for only short-term use for the treatment of obesity. Herbal preparations are not recommended as part of a weight loss program. These preparations have unpredictable amounts of active ingredients and unpredictable, and potentially harmful, effects.
source: "Table 6. Weight Loss Drugs," in The Practical Guide: Identification, Evaluation, and Treatment of Overweight and Obesity in Adults, National Institutes of Health, National Heart, Lung, and Blood Institute, North American Association for the Study of Obesity, October 2000, http://www.nhlbi.nih.gov/guidelines/obesity/practgde.htm (accessed January 12, 2006)
Sibutramine (Meridia)5, 10, 15 mgNorepinephrine, dopamine, and serotonin reuptake inhibitor.Increase in heart rate and blood pressure.
10 mg orally every day to start, may be increased to 15 mg or decreased to 5 mg
Orlistat (Xenical)120 mgInhibits pancreatic lipase, decreases fat absorption.Decrease in absorption of fat-soluble vitamins; soft stools and anal leakage.
120 mg orally three times a day before meals

Another experimental weight-loss drug, rimonabant, blocks the "munchie receptor" believed to stimulate appetite among people who smoke marijuana. Preliminary data, announced by the French pharmaceutical company Sanofi-Synthelabo in March 2004, showed that patients receiving a daily dose of rimonabant lost an average of twenty pounds (9.07 kg) in a year. By April 2005, the results of a yearlong multicenter study of 1,507 overweight or obese adults showed that subjects that took rimonabant lost more weight than subjects who attempted to lose weight via diet alone. The rimonabant group also had greater improvements in high-density lipoprotein cholesterol and triglycerides. Other cardiovascular risk factors are improved as well, including dyslipidemia and insulin resistance (Luc Van Gaal et al., "Effects of the Cannabinoid-1 Receptor Blocker Rimonabant on Weight Reduction and Cardiovascular Risk Factors in Overweight Patients: One-year Experience from the RIO-Europe Study," Lancet, vol. 365, no. 9,468, April 16, 2005). Since rimonabant blocks cravings, its potential as a smoking-cessation aid is also under investigation.

In 2005 there were also promising preliminary findings from a twenty-eight-day trial of a drug from Arena Pharmaceuticals known only as APD356. Subjects taking the drug lost an average of 2.9 pounds during the twenty-eight-day trial compared with a loss of 0.7 pounds by subjects who took a placebo (http://www.arenapharm.com/wt/page/apd356). The drug acts by stimulating receptors in the hypothalamus, a part of the brain that plays a key role in regulating food intake and metabolism.

Non-Prescription Weight-Loss Aids

The withdrawal of fenfluramine from the market prompted many consumers to seek alternative weight-loss aids, including herbal preparations that were marketed as dietary supplements and available over-the-counter. Some preparations, such as such as Stacker 2 and Metabolife 356, combined ephedra, caffeine, and other ingredients. Ephedra (also known by its traditional Chinese medicine name, ma huang) is a naturally occurring substance that comes from botanicals. Products containing ephedra and ephedrine have been promoted to accelerate weight loss, increase energy, and improve athletic performance. The principal active ingredient in ephedrine is an amphetamine-like compound that stimulates the nervous system and heart. Because ephedrine has some anorectic and thermogenic properties, it may induce weight loss in some people, and some studies have shown that when ephedrine is combined with caffeine, the combination may lead to even more weight loss.

During 2003 the FDA and NIH investigated reports of adverse effects linked to ephedra use. A RAND Corporation study commissioned by the NIH concluded that there was only limited evidence of health benefits resulting from ephedra use. These benefits did not outweigh the serious risks posed by its association with heart palpitations, psychiatric and upper gastrointestinal effects, tremors, and insomnia, especially in formulations in which it was combined with caffeine, or taken with other stimulants. The RAND researchers reviewed 16,000 adverse events and identified two deaths, four heart attacks, nine strokes, one seizure, and five psychiatric cases in which ephedra appeared to be the causative agent.

Another study, "The Relative Safety of Ephedra Compared with Other Herbal Products" (Annals of Internal Medicine vol. 138, no. 6, March 18, 2003), conducted by Stephen Bent and his colleagues, compared the risk for adverse events attributable to ephedra and other herbal products. The investigators found that while ephedra products comprised less than 1% of all dietary supplement sales, they accounted for 64% of adverse events associated with dietary supplements. They concluded that "the risk for an adverse reaction after the use of ephedra is substantially greater than with other herbal products."

In July 2003 the Federal Trade Commission generated more negative publicity for the dietary supplement when it charged marketers of weight-loss products that contain ephedra with making deceptive efficacy (effectiveness) and safety claims. The Federal Trade Commission actions deemed as examples of false advertising claims that ephe-dra causes rapid, substantial, and permanent weight loss without diet or exercise, and that "clinical studies" or "medical research" proved these claims. The Commission also challenged claims that the ephedra weight-loss products are "100% safe," "perfectly safe," or have "no side effects."

On December 30, 2003, the U.S. Department of Health and Human Services and the FDA notified manufacturers of dietary supplements containing ephedra that the sale of these dietary supplements would be banned sixty days following publication of the year-end notice. The same day, the FDA issued an alert to consumers advising them to stop using ephedra products immediately.

During the first months of 2004, dieters flocked to health food stores and Internet sites selling dietary supplements and bought entire inventories of supplements containing ephedra in anticipation of the ban of its sale as early as April 12, 2004. Many of the supplements' fans asserted that the ban was prompted by the publicity surrounding the ephedra-related death of Baltimore Orioles pitcher Steve Bechler on February 17, 2003. Bechler was twenty-three years old when he collapsed from heatstroke at the Orioles' spring training camp in Florida. Two weeks later the FDA ordered warning labels be placed on products containing ephedra, and set in motion plans to ban its sale.

Many health professionals and consumer watchdog agencies such as the advocacy group Public Citizen applauded the FDA action but observed that the FDA first proposed warning labels and a dosage curb for ephedra in 1997, but the supplement industry effectively blocked the move. The December 2003 action was a historic occasion—the first time the FDA completed the steps necessary to ban the sale of a dietary supplement.

WILL HOODIA BE THE NEXT BEST THING FOR DIET ERS?

With ephedra withdrawn from the market, dieters anxiously awaited the introduction of another nonpre-scription drug to replace it. In 2003 reports of an appetite suppressant derived from hoodia, a bitter-tasting cactus that grows in the South African Kalahari desert, generated interest and excitement. The San Bushmen of the Kalahari, one of the world's oldest and most primitive tribes, have been eating hoodia for thousands of years, to stave off hunger during long hunting trips.

The plant contains a molecule, called p57, which is thought to act on the hypothalamus to mimic the sense of satiety that normally results only from eating food. The first clinical trials of hoodia were considered successful when subjects given hoodia consumed an average of 1,000 calories fewer per day than those given placebo. Phytopharm, the company that holds the rights to extracting p57 from hoodia, expects to market products containing hoodia by 2007. In the meantime, following a segment about hoodia that aired on the CBS newsmagazine 60 Minutes (November 21, 2004), demand for hoodia skyrocketed. In response, many importers introduced products that claimed to contain hoodia, and by 2006, dozens of Web sites offered pills, powders, and liquids containing various amounts of hoodia.

SURGERY

Weight-loss surgery is considered a treatment option only for people for whom all other treatment methods have failed and who suffer from clinically severe obesity—BMI of 40 or greater or BMI of 35 or greater in the presence of comorbidities. (Clinically severe obesity was formerly known as morbid obesity, indicating its potential to cause disease.) Two types of surgical procedures have been demonstrated effective in producing weight loss maintained for five years: "restrictive" techniques, which restrict gastric volume, and "malabsorptive" procedures, which not only limit food intake but also alter digestion. An example of the first type is banded gastroplasty, in which an inflatable band that can be adjusted to different diameters is placed around the stomach. The Roux-en-Y gastric bypass is an example of the second type. (See Figure 6.4.) On average, patients maintain a weight loss of 25% to 40% of their preoperative body weight after these procedures.

An NIH review of five randomized clinical trials (studies in which participants are assigned by chance to separate groups to compare the outcomes of different treatments to determine which is most effective) found that patients who received obesity surgery lost 10 kg to 159 kg (22.05 to 350.53 pounds) over twelve to forty-eight months; however, the surgeries are not without risk, so health-care professionals generally recommend surgery only when the risks of obesity far outweigh the risks associated with the surgery. According to the National, Heart, Lung, and Blood Institute, surgical complications vary depending on the weight and overall health of the surgical patient. Young people without comorbidities and BMI equal to or less than 50 have the lowest reported mortality rates—less than 1%. Not unexpectedly, those with BMI equal to or greater than 60 with comorbidities such as diabetes or high blood pressure have mortality rates of 2% to 4%.

People who undergo weight-loss surgeries require lifelong medical monitoring. After surgery they are no longer able to eat in the way to which they were accustomed. Those who have undergone gastric bypass experience "dumping syndrome" with symptoms such as sweating, palpitations, lightheadedness, and nausea when they ingest significant amounts of calorie-dense food, and most become conditioned not to eat such foods. Patients who have had gastric restriction surgery are unable to eat more than a limited amount of food at a single sitting without vomiting, and must eat several small meals per day to maintain adequate nutrition. Those who do not adhere to a prescribed regimen of vitamins and minerals may develop vitamin and iron deficiencies. There also are postoperative and long-term complications of surgery such as wound infections, problems such as hernias at the incision site, and gallstones. Generally, however, patients fare extremely well, experiencing dramatic improvement and even complete resolution of diabetes, hypertension, and infertility, as well as improved mobility, self-esteem, and overall quality of life.

In "Surgery for Obesity: Demand Soars Amid Scientific, Ethical Questions" (Journal of the American Medical Association, vol. 289, no. 14, April 9, 2003), Mike Mitka noted that ethical and scientific questions about obesity surgery remain unanswered. Mitka observed that a 1991 Consensus Statement by the NIH that established criteria for eligibility for surgical treatment of morbid obesity opened the door for insurance coverage and precipitated an explosive increase in its use. About 47,000 surgeries for treatment of morbid obesity were performed in the United States in 2001, approximately 63,000 surgeries were performed in 2002, and about 98,000 in 2003. He noted that the demand for the surgery was so great that many hospitals had yearlong waiting lists of hundreds of patients.

Mitka questioned whether the science is keeping pace with the popularity of the procedures, observing that fundamental questions about the surgery and its long-term consequences are unanswered. These include a complete understanding of the precise mechanisms whereby surgical treatment results in weight reduction; mechanisms underlying improvement in comorbid risk factors or disease; safety and efficacy of surgery in defined patient subgroups; safety and efficacy of different surgical procedures; and the impact of surgery on subsequent pregnancy. Issues such as the maintenance of weight loss and the long-term effects of altering nutrient absorption also remain unresolved.

Troubling questions about reimbursement and payment for the surgery also remain. With some surgeons performing as many as 400 surgeries per year for fees as high as $10,000 per procedure, the practice is extremely lucrative. In 2005 the cost of surgery and related care ranged from $20,000 to $50,000. In light of the increasing number of obese adults in the United States and the willingness of many to pay cash if they do not have insurance or they have been denied coverage, some surgeons may be motivated by financial interests to perform increasing numbers of procedures. This ethical issue is heightened by the proliferation of print and electronic media advertising of the surgery by physicians and hospitals along with endorsement of the procedure by celebrities. Carnie Wilson of the band Wilson Phillips, and daughter of Beach Boy Brian Wilson, has been the most outspoken celebrity proponent of gastric bypass surgery since undergoing the procedure in 1999 and slimming down from 300 to 150 pounds. Today Show weather reporter Al Roker had gastric bypass surgery in March 2001, and comedian Roseanne had gastric bypass surgery in 1998. Although some industry observers feel that celebrity success stories have raised the visibility of gastric bypass surgery and reduced the stigma associated with seeking treatment for obesity, others fear that media fanfare will prompt increasing numbers of people who are obese to forgo less drastic treatment options in favor of the surgery that media celebrities endorse.

Number of Surgeons and Surgeries Soars

The American Society for Bariatric Surgery (http://www.asbs.org/) reports that its membership has risen steadily from 162 in 1992 to 1,364 in 2005. In 1992, 16,000 bariatric procedures were performed; in 2005 the number was estimated to be in excess of 150,000. For thousands of patients, the weight-loss surgery has eliminated debilitating diseases and improved the quality of life. With the number of candidates for bariatric surgery increasing, the number of procedures is expected to continue to grow, even in view of data that reveals that the risks are greater than previously believed.

One study reported that one in five patients suffered complications after surgery. For one in twenty patients, the complications were serious, including heart attacks and strokes. Another recent study said the mortality rate for the most common type of bariatric surgery, gastric bypass, was one in 200-higher than for coronary angioplasty, a procedure to open blocked heart vessels. Because bariatric surgery is increasingly common, there may be more complications and deaths overall, even if the risk associated with each individual procedure decreases (Robert Steinbrook, "Surgery for Severe Obesity," New England Journal of Medicine, vol. 350, no. 11, March 11, 2004).

One survey found that even the risk of death does not dissuade many patients from undergoing bariatric surgery (Christina Wee et al., "Assessing the Value of Weight Loss among Primary Care Patients," Journal of General Internal Medicine, vol. 19, no. 12, December 2004). In an effort to quantify the value people place on modest weight loss, researchers at Harvard Medical School interviewed 366 patients at a large hospital-based primary care practice, one-third of whom were obese. The subjects were asked to imagine a treatment that would guarantee them effortless weight loss of varying amounts of weight. For each amount, they were asked, would they be willing to accept a risk of death to achieve it? If so, how much of a risk of death?

Willingness to risk death or trade years of life to lose weight significantly increased with higher BMI, and the more weight the subjects imagined they could lose, the greater the risk they would take to achieve it. Nineteen percent of overweight and 33% of obese people said they would risk death for even a modest 10% weight loss, compared with just 4% of normal weight subjects willing to risk death to lose 10% of their weight.

Many of the overweight and obese participants in the Harvard survey also said they would give up some of their remaining years of life if they could live those years weighing slightly less. Thirty-one percent of obese patients and 8.3% of overweight patients said they would trade up to 5% of their remaining lives to be 10% thinner. The researchers concluded that many people, especially those who are obese, value modest weight loss and they exhorted physicians to emphasize the benefits of modest weight loss when counseling their patients.

COUNSELING AND BEHAVIORAL THERAPY

Weight-loss counseling and behavioral therapy aim to assist people to develop the skills needed to identify and modify eating and activity behaviors, and change thinking patterns that undermine weight-control efforts. Behavioral strategies include self-monitoring of weight, food intake, and physical activity; identifying and controlling stimuli that provoke overeating; problem identification and problem solving; and using family and social support systems to reinforce weight-control efforts. Counseling and behavioral therapy are often perceived as necessary components of comprehensive weight-loss treatment, but are also viewed as labor intensive because educating and supporting people seeking to lose weight is time consuming. The effort also requires the active participation of everyone who may be involved in treatment—the affected individuals, their families, physicians, nurses, nutritionists, dieticians, exercise instructors, and mental health professionals. In view of the considerable resources that must be allocated to deliver counseling and behavioral therapy, it is important to know if these approaches effectively promote weight loss.

Michael J. Devlin and his colleagues conducted an evaluation of obesity treatments and reported their findings in "Obesity: What Mental Health Professionals Need to Know" (American Journal of Psychiatry, vol. 157, no. 6, June 2000). The authors observed that comprehensive behavioral weight-control programs to improve eating habits and increase physical activity are considered the "treatments of choice" for overweight and moderately obese individuals because their use not only can reduce body weight by fifteen to twenty pounds and decrease depression and body image dissatisfaction but also can enhance self-esteem and interpersonal functioning. Unfortunately, the favorable results are not enduring. At one-year follow-up evaluations, people who had received behavioral treatment with dietary restriction regained 35% to 50% of their weight loss, both in research clinics and in the general population. Five-year follow-ups revealed that the vast majority of patients had regained all of the weight they had lost.

Like most other obesity researchers, Devlin and his colleagues do not consider psychotherapy as a primary treatment for obesity; however, they acknowledge the effectiveness of cognitive behavioral therapy and interpersonal therapy in normalizing eating and reducing distress in obese patients with binge-eating disorder, although neither approach is associated with significant weight loss. Further, since psychotherapy may enhance self-acceptance, and greater self-acceptance and overall self-esteem are prerequisites for developing and maintaining the motivation to adhere to weight-loss treatment, psychotherapy may be an important component of treatment for some overweight and obese people. The authors stated that "Enhancing self-acceptance may not only provide a more compassionate approach to what has proved a refractory problem, but might also lead to more lasting reductions in weight by virtue of helping patients to accept only modest weight loss and improve compliance with health-relevant eating and exercise behaviors."

Kathleen M. McTigue and her colleagues considered the evidence supporting the efficacy of counseling and behavioral therapy as well as other treatment methods and reported their findings in "Screening and Interventions for Obesity in Adults: Summary of the Evidence for the U.S. Preventive Services Task Force" (Annals of Internal Medicine, vol. 139, no. 11, December 2, 2003). The investigators reported that counseling to promote change in diet, exercise, or both, and behavioral therapy to help patients acquire the skills, motivations, and support to change diet and exercise patterns enabled obese patients to achieve modest but clinically significant, sustained (one to two years) weight loss. Further, they observed that because control groups also frequently received some form of counseling, education, or support, they might have underestimated the effectiveness of counseling. Not unexpectedly, more intensive programs, with more frequent contact, were generally more successful, as were those incorporating behavioral therapy.

Interestingly, the investigators found that treating patients on an individual rather than a group basis did not appear to affect outcomes. This finding offers credence to the theory that the benefits of mutual aid and peer support provided by group programs may be as powerful as the personalized, one-to-one attention afforded patients in individual counseling sessions. If this is true, then group programs might be a laborsaving, cost-effective alternative to individual weight-loss counseling.

The investigators concluded that "All obesity therapies carry promise and burden, which must be balanced in clinical decision-making. Counseling approaches appear the least harmful and produce modest, clinically important weight loss but entail cost in time and resources. Pharmacotherapy promotes modest additional weight loss, but long-term drug use may be needed to sustain this benefit, and long-term adverse events and appreciable cost are unknown. Only surgical options consistently result in substantial long-term weight reduction; however, they carry a low risk for severe complications and are expensive. Body size, health status, and weight-loss history all may influence obesity treatment."

Comparing Weight-Loss Using a Self-Help Program and a Commercial Program

Stanley Heshka and his colleagues reported the results of their research to determine the efficacy of commercial weight-loss programs in "Weight Loss with Self-Help Compared with a Structured Commercial Program: A Randomized Trial" (Journal of the American Medical Association, vol. 289, no. 14, April 9, 2003). Their study randomly assigned one group of obese men and women to a self-help program consisting of two twenty-minute counseling sessions with a nutritionist and provision of self-help resources such as public library materials, Web sites, and telephone numbers of health organizations that offered free weight-control information. The other group was assigned to attend Weight Watchers, a commercial weight-loss program consisting of a food plan, an exercise plan consistent with NIH-recommended physical activity guidelines, regular weight monitoring, printed educational materials, and a behavior modification plan, delivered at weekly meetings.

Subjects were evaluated regularly during the course of the two-year study—at twelve, twenty-six, fifty-two, seventy-eight, and 104 weeks. The primary outcome measure used to evaluate the effectiveness of the programs was change in body weight; however, BMI, waist circumference, and body-fat as quantified by bioimpedance analysis (electrical resistance) were also recorded. Other secondary measures were blood pressure, total cholesterol, HDL cholesterol, triglycerides, insulin, and quality of life measured using the Medical Outcomes Study Short-Form 36 Health Survey and Impact of Weight on Quality of Life Questionnaire.

After one year of participation in the study, subjects in the commercial program had greater weight loss than those in the self-help group. Similarly, waist circumference and BMI decreased more in the commercial group than in the self-help group. Blood pressure and serum insulin showed greater improvement in the commercial group compared with self-help at year one, but only insulin was significantly different at year two. Total cholesterol and the HDL/total cholesterol ratio improved in both groups. The commercial group maintained a weight loss of 4.3 to 5.0 kg (9.48 to 11.02 pounds) at the end of the first year and was 2.7 to 3.0 kg (5.95 to 6.61 pounds) lower than initial weight at the end of the second year. Subjects who attended 78% or more of the commercial group sessions maintained a mean weight loss of almost 5 kg (11.02 pounds) at the end of the two-year study. The investigators concluded that while the structured commercial weight-loss program provided only modest weight loss, it was more effective than brief counseling and self-help for overweight and obese adults over a two-year period.

Weight-Loss Counseling to Change Behavior

The NIH designed a practical protocol, known as an algorithm, for obtaining and organizing information necessary for effective weight-loss counseling. The algorithm is based on the "five As":

  • Assessing obesity risk
  • Asking about readiness to lose weight
  • Advising about a weight-control program
  • Assisting to establish appropriate intervention
  • Arranging for follow-up

The Practical Guide to the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults recommends that health-care professionals consider a variety of psychosocial, environmental, and health-related issues when performing a "behavioral assessment" of an individual for whom weight loss is indicated. These issues include:

  • Whether the individual is seeking to lose weight on their own or in response to pressure from family members, an employer, or a physician. This is an important consideration because people who feel coerced into seeking weight-loss treatment are not as likely to achieve success as those who seek it on their own initiative.
  • Identifying the source of the individual's desire to lose weight to better understand his or her motivation and goals. Since many people have suffered from overweight or obesity for years before seeking treatment, pinpointing the stimulus to lose weight can assist the health-care professional to motivate and support the individual's weight-loss efforts.
  • Assessing the individual's stress level to determine if such external stressors as family, financial, or work-related problems might prevent the individual from concentrating on weight loss. It is also important to determine if the individual is suffering from depression or other mental health problems because it is usually advisable to treat mood disorders or other mental health problems before embarking on a weight-loss program.
  • Evaluating the individual for the presence of an eating disorder such as binge eating that may coexist with overweight or obesity. People suffering from eating disorders are more likely to require psychological treatment and nutritional counseling to ensure the success of weight-loss programs than those who do not have eating disorders.
  • Determining the individual's understanding of the lifestyle and other changes required for weight loss. The success of treatment hinges on the individual's ability to successfully make the required changes, so it is vital to develop a treatment plan that includes realistic activities such as gradually increasing physical activity that the individual agrees are attainable.
  • Setting and agreeing upon realistic weight-loss goals and objectives. If an obese individual has unrealistic expectations about the amount of weight that will be lost, then he or she may become discouraged and abandon efforts to lose weight. Health professionals should temper unrealistic expectations by informing individuals about the considerable health and lifestyle benefits of even modest weight loss.

Successful weight loss is more likely to occur when health-care professionals—physicians, nurses, nutritionists, dieticians, and mental health professionals—actively involve people seeking to lose weight in a collaborative effort to establish short-term goals and attain them. "Shaping" is a behavioral technique in which a series of short-term objectives are identified that ultimately lead to a treatment goal, such as incrementally increasing physical activity from ten minutes per day to forty-five minutes per day over time. "Self-monitoring" is the practice of observing and recording behaviors such as caloric intake, food choices, amounts consumed, and emotional or other triggers to eat as well as physical activity performed and daily or weekly monitoring of body weight. Figure 6.5 is an example of the weekly food and activity diary used to self-monitor progress.

Finally, The Practical Guide to the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults reminds health professionals to acknowledge the challenges of accomplishing weight loss and encourages everyone involved in treatment to "focus on positive changes and adapt a problem-solving approach toward shortfalls. Emphasize that weight control is a journey, not a destination, and that some missteps are inevitable opportunities to learn how to be more successful."

Weight-Loss Counseling Online

An expanding array of diet, counseling, and support group programs are available on the Internet; however, little research has compared them or determined their efficacy. Although behavioral counseling has been demonstrated effective for weight loss to reduce the risk of developing diabetes, many public health professionals contend that the large number of people at risk requires a less labor-intensive approach than individual face-to-face-counseling. Deborah Tate and her colleagues at the Brown University School of Medicine, Miriam Hospital, Weight Control and Diabetes Research Center, sought to determine whether varying types of Internet services would prove to be viable alternatives to in-person counseling. They compared the effects of an Internet weight-loss program alone with an Internet program that also provided behavioral counseling via e-mail for one year to people at risk for Type 2 diabetes. Their study was described in "Effects of Internet Behavioral Counseling on Weight Loss in Adults at Risk for Type 2 Diabetes: A Randomized Trial" (Journal of the American Medical Association, vol. 289, no. 14, April 9, 2003).

Subjects were randomly assigned to a basic Internet weight-loss program or an Internet plus behavioral e-counseling program. Both groups received a one-hour introductory group weight-loss counseling session that consisted of standard behavioral weight-control instruction on diet, exercise, and behavior change. Recommendations included calorie-restricted diets of between 1,200 and 1,500 calories per day, fat intake of 20% or fewer calories, and a minimum of physical activity sufficient to expend 1,000 calories per week. All participants were encouraged to self-monitor their diets and exercise using diaries and calorie books provided. Both groups accessed the same Web site, which provided a tutorial on weight loss, a new tip and link each week, and a directory of selected Internet weight-loss resources. Each week, all participants received an e-mail reminder to submit their body weight and received weight-loss information.

Subjects in e-counseling submitted calorie and exercise information and received weekly e-mail behavioral counseling and feedback from counselors who had earned master's or doctoral degrees in health education, nutrition, or psychology. During the first month of the yearlong study, counselors e-mailed subjects five times each week, and sent weekly e-mails for the remaining eleven months. Counselor e-mail messages offered feedback on the self-monitoring record, reinforcement, recommendations for change, and answers to questions, as well as general support and encouragement. Subjects who failed to submit reports were sent personal follow-up e-mail messages.

The primary outcome measure used to compare the groups was change in body weight from baseline to twelve months. Weight was measured at baseline and at three, six, and twelve months, and the behavioral e-counseling group had greater reductions in weight than the basic Internet group at each weigh-in. Although both groups reported significant reductions in caloric intake, the behavioral e-counseling group reduced the percentage of calories consumed from fat by 4% compared with a 1% reduction in the basic Internet group. The investigators concluded that the addition of e-mail behavioral counseling doubled the percentage of initial body weight lost compared with an Internet intervention without individualized therapist guidance.

Another evaluation of weight-loss programs included the results of a randomized trial of eDiets.com, an Internet-based intervention, which charges participants $65 for three months of online counseling and diet education. The eDiets.com service offers thirteen diets and provides recipes based on clients' dietary preferences. The company also offers a mutual support program in the form of online chats with other clients as well as e-mail advice from psychologists and dieticians.

After participating in eDiets.com for one year, participants lost 1.1% of their initial weight compared with a 4% loss among a control group simply given a self-help manual about weight management (Adam Gilden Tsai and Thomas A Wadden, "An Evaluation of the Major Weight Loss Programs in the United States" Annals of Internal Medicine, vol. 142, no. 1, January 4, 2005). The researchers also observed that these results likely represented a best-case scenario for eDiets.com since the participants were provided with eleven on-site visits to assess their weight and five consultations with a psychologist. These extra services, which are not offered to average subscribers, may have enhanced participants' motivation and adherence to their diets.

Complementary and Alternative Therapies

Many complementary and alternative medicine practices such as yoga, Dahn—a holistic mind-body training method—and "mindful eating," which teaches greater awareness of bodily sensations such as hunger and satiety and helps people identify "emotional eating," have been used to promote weight loss. Acupuncture and hypnosis are, however, the only alternative medical practices that have been studied as potential treatments for obesity. Several studies reported that acupuncture—the Chinese practice of inserting extremely thin, sterile needles to any of 360 specific points on the body—did not appear to have any benefit greater than placebo.

Hypnosis is an altered state of consciousness. It is a state of heightened awareness and suggestibility and enables focused concentration that may be used to alter perceptions of hunger and satiety, and to modify behavior. Some dieters swear by hypnosis, which today is considered mainstream treatment for addictions and overeating. There are conflicting data about its effectiveness—some studies found that it adds little, if any, benefit beyond that of placebo. Others concluded that hypnosis may have some initial benefit for people seeking weight loss, but that it had very little sustained effect.

In "Hypnotic Enhancement of Cognitive-Behavioral Weight Loss Treatments—Another Meta-Reanalysis" (Journal of Consulting and Clinical Psychology, vol. 64, no. 3, June 1996), University of Connecticut psychologist Irving Kirsch recalculated data from five previous studies that examined the value of hypnosis in weight-loss treatment. Kirsch asserted that his analysis found that the mean weight loss reported in the five studies indicated that hypnosis can more than double the effects of a cognitive/behavioral treatment. He also found that the impact of hypnosis increased over time, suggesting that it might be useful for long-term maintenance of weight loss. He qualified his findings by noting that hypnosis appeared effective only in conjunction with cognitive/behavioral treatment, and he conceded that "obese people would still be obese after losing the amount of weight reported in these studies."

MIGHT WEIGHT LOSS BE HARMFUL?

Successful weight-loss treatments generally result in reduced blood pressure, reduced triglycerides, increased HDL cholesterol, and reduced total cholesterol and LDL cholesterol. Weight loss of as little as 5% to 10% of initial weight produces measurable health benefits and may prevent illnesses among people at risk. These findings suggest that treatment should not exclusively focus on the medical consequences of obesity, but obesity itself should be treated. The NIH recommends weight loss for people with BMI greater than 30 and for those with BMI greater than 25 with two or more obesity-related risk factors. The NIH guidelines recommend that for people with BMI between 25 and 30 without other risk factors, the focus should be prevention of further weight gain, rather than weight loss.

In "Obesity: What Mental Health Professionals Need to Know," Devlin reported that critics cite the health and psychological risks of "weight cycling"—continuously pursuing weight loss in the diet-weight loss/weight regain cycle known as "yo-yo dieting" as even greater than the risks associated with obesity. They assert that multiple unsuccessful efforts to lose weight demoralize people, make future weight loss even more challenging, and that dietary treatment of obesity may trigger or worsen binge eating among people who are obese. They also offer several studies that have found an association between weight cycling and increased morbidity and mortality as evidence of the dangers of dieting.

In "Screening and Interventions for Obesity in Adults: Summary of the Evidence for the U.S. Preventive Services Task Force" (Annals of Internal Medicine, vol. 139, no. 11, December 2, 2003), Kathleen McTigue and her colleagues also reviewed the studies that revealed a link between weight cycling and mortality. The investigators found that some studies failed to distinguish between intentional and unintentional weight loss. In the research considering the relationship between weight cycling with intentional weight loss, some studies have found unfavorable effects on coronary heart disease and its risk factors and others have not. They also found data suggesting that weight-cycling risk increases inversely with BMI—the higher the BMI, the lower the risk of weight cycling. If these findings are correct, then people suffering from obesity as opposed to overweight are at less risk of morbidity and mortality attributable to weight cycling.

Is It Better to Be Overweight?

Two studies published in the April 2004 issue of the Journal of the American Medical Association found less risk associated with overweight than previously thought. One study, conducted by investigators from the National Cancer Institute and the Centers for Disease Control and Prevention found that increased risk of death from obesity was mostly among the extremely obese, a group constituting of just 8% of Americans. The researchers also found that extreme thinness carried a slight increase in the risk of death. The study did not explain how or why being slightly overweight afforded protection but researchers speculate that it is because most people die when they are over 70. Being mildly overweight in old age may be protective, because it gives rise to more muscle and more bone.

The other study examined forty-year trends in cardiovascular disease (CVD) risk factors by BMI groups among adults aged twenty to seventy-four years found that except for diabetes, CVD risk factors have declined considerably over the past forty years in all BMI groups. Although obese people still have higher risk-factor levels than lean people, the levels of these risk factors are much lower than in previous decades. The investigators observed that obese people today have better CVD risk factor profiles than their leaner counterparts did twenty to thirty years ago; however, they suggested that other factors, such as effective treatment to reduce cholesterol and blood pressure as well as the decreased prevalence of smoking, might explain the improved profiles of obese people (Edward W. Gregg et al., "Secular Trends in Cardiovascular Disease Risk Factors According to Body Mass Index in U.S. Adults" Journal of the American Medical Association, vol. 293, no.15, April 20, 2005).

While the government continued to warn that excess weight is a major threat to the 65% of adult Americans who are either overweight or obese, that is not the message that many people heard in the report from the CDC researchers. The media claimed that the public interpreted these data as an endorsement of overweight and a reason to abandon, or at least relax, their efforts to diet and lose weight. Interviewed for an article in the New York Times in May 2005, Dan Mindus, a senior analyst for the Center for Consumer Freedom, a lobbying group underwritten by the food industry, asserted, "The federal government had told us that your love handles were going to kill you. Now people understand that being overweight is probably a little healthier than being thin" (Timothy Egan, "With Potbellies Back In, Buffet Pots Are Humming," New York Times, May 3, 2005).

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Physical Activity, Drugs, Surgery, and Other Treatment for Overweight and Obesity

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