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Diet and Exercise: Still the Best Medicine for Losing Weight or Keeping Fit

Worst Pills, Best Pills Newsletter article October, 2012

Earlier this year, the Food and Drug Administration (FDA) approved two new drugs for weight loss: topiramate-phentermine (QSYMIA) and lorcaserin (BELVIQ). These drugs are the latest in a long line of drugmakers’ previously failed attempts to find a safe and effective diet pill that will help Americans shed pounds easily. Every previous drug approved for weight loss in the U.S. has been commercially unsuccessful because of serious safety problems and lack of a significant benefit. Those...

Earlier this year, the Food and Drug Administration (FDA) approved two new drugs for weight loss: topiramate-phentermine (QSYMIA) and lorcaserin (BELVIQ). These drugs are the latest in a long line of drugmakers’ previously failed attempts to find a safe and effective diet pill that will help Americans shed pounds easily. Every previous drug approved for weight loss in the U.S. has been commercially unsuccessful because of serious safety problems and lack of a significant benefit. Those taken off the market have almost always been pulled because of serious cardiovascular risks such as heart attack, stroke or heart valve damage.

The time has come to put an end to the search for a “magic pill” and put the focus back on the only proven safe and effective methods of healthy weight loss: diet and exercise.

Dangerous diet drugs

On July 17, 2012, the combination topiramate-phentermine (Qsymia) was approved for weight loss in obese — or less obese but overweight — adults who also have at least one weight-related health condition (such as diabetes or high blood pressure). Lorcaserin (Belviq) was approved on June 27, 2012, for the same indication. Public Citizen opposed FDA approval of the two new drugs because in each case the drugs are likely to cause serious side effects. Heart valve damage is an adverse effect of lorcaserin, a drug related to withdrawn drug fenfluramine (see shaded box below). Both lorcaserin and topiramate-phentermine can cause birth defects, memory impairment, and decreased concentration/attention. Other adverse effects are that Qsymia can dangerously increase and Belviq can lower heart rate. We rate both of these as DO NOT USE drugs.

When they appear on the market (later this year or in early 2013), these two new diet drugs will join a small number of unsafe and minimally effective diet drugs still on the market. Among those drugs still on the market are XENICAL and ALLI, both of which contain orlistat, a drug that prevents the body from absorbing fats. Public Citizen has petitioned the FDA to ban orlistat because it can cause liver damage, renal failure and acute pancreatitis. Orlistat is already commercially unpopular because of its more common gastrointestinal side effects, which include fecal incontinence and loose, oily stools.

History of failed diet drugs

  • Fenfluramine was approved in the 1970s and promised to help people lose weight by activating a serotonin receptor in the brain to reduce appetite. The drug produced only modest, short-term weight loss and failed to attract many users until the 1990s, when it re-emerged alongside a new, closely related drug, dexfenfluramine. Both drugs were prescribed as the “fen” part of the popular diet drug combination fen-phen — or dexfen-phen, using dexfenfluramine. (A second drug, phentermine, now an ingredient in the newly approved topiramate-phentermine combination, formed the “phen” part of the combination).

    As more people began using fen-phen — prescribed separately because the two ingredients were never approved by the Food and Drug Administration (FDA) as a combination drug — it became clear that fenfluramine and dexfenfluramine (but not phentermine) actually caused severe, life-threatening side effects, including heart valve damage and a potentially fatal adverse reaction of the lungs known as primary pulmonary hypertension. Fenfluramine and dexfenfluramine were withdrawn from the market in September 1997.
  • Phenylpropanolamine (PPA, found in now-discontinued versions of DEXATRIM) was marketed over the counter as an appetite suppressant. The FDA pulled the drug from the market in 2000 after evidence surfaced linking the drug with hemorrhagic (bleeding) strokes.
  • Ephedra. Undaunted, the weight-loss industry increased its focus on ephedra, widely marketed as a dietary supplement for weight loss and body building. Ephedra was a compound similar to PPA and was included in the subsequent version of DEXATRIM, called NATURAL DEXATRIM. Public Citizen petitioned the FDA to ban ephedra in 2001, and the FDA finally did so in December 2003, after ephedra had been found to cause 33 deaths among otherwise healthy young military personnel.
  • Sibutramine (MERIDIA) is another dangerous weight-loss drug that caused life-threatening risks and was only minimally effective. Public Citizen petitioned the FDA to ban sibutramine in 2002 and petitioned again for a ban in 2009, after a large, randomized controlled trial showed that the drug increased the risk of heart attack, stroke and death.

    Following the ban of sibutramine in Europe in early 2010, a widely respected British endocrinologist wrote in the British Medical Journal: “The fate of sibutramine reminds us how little antiobesity drugs have had to offer — at best, a reduction of a few per cent in the total burden of excess weight carried until death. … it has always seemed unlikely that a magic bullet could ever switch off food intake without hitting something vital.”

    The drug was finally pulled from the market in the U.S. in 2010.

FDA regulation

There is no evidence that any weight-loss drug approved by the FDA actually prevents the negative health outcomes associated with obesity, such as heart disease, stroke or diabetes. This is because the FDA does not require these types of benefits when approving a diet pill.

This policy has resulted in a long history of the FDA approving diet drugs without a full understanding of the drugs’ health impacts, only to withdraw them when the agency discovers (albeit too late) that the medications do more harm than good. (See shaded box below.)

Weight-loss fads

Some doctors (and nonhealth professionals) promote weight-loss diets that focus on specific types of food (such as cutting out fats or carbohydrates). These diets have been the subject of countless, often best-selling, books generically and euphemistically entitled “The 30-Day [fill in the blank] Diet.”

The fact that said diets are ultimately replaced by yet another such book-diet fad suggests some problem with this approach. While there is some evidence that specific diets can help with certain conditions — such as low-salt diets for hypertension — scientists still can’t say whether one particular type of food is better for achieving weight loss than any another.

As Dr. George A. Bray, a noted expert on weight loss, stated in a recent editorial in The Journal of the American Medical Association, when it comes to weight loss, “calorie restriction [cutting calories] is more important than diet composition.” Significant weight loss can be achieved with diets that are lower in calories and balanced between food groups — with lots of protein, fiber, fresh fruit and vegetables — and low to moderate amounts of fat.

Healthy weight loss

Weight loss is an important public health goal because obesity is related to other negative health outcomes, such as diabetes, hypertension, heart attack and stroke. A person who loses weight by using healthy methods can reduce disease risk, improve quality of life and, probably, live longer. But healthy weight loss has never been found to come from a pill.

Instead, the only proven, effective way to lose weight and improve health is through diet and exercise. Research has shown that when a patient at risk for heart problems or diabetes works to lose weight through diet and exercise, that patient can achieve significant health improvements. The benefits of such activity include lowered blood pressure, decreased risk of diabetes and heart disease, better levels of good cholesterol, and improved overall fitness. Some health benefits are noticeable even if only a modest amount of weight is lost (just 6 percent, or 15 pounds for a 250-pound person).

In June 2012, the U.S. Preventive Task Force released new recommendations identifying the most successful strategies for weight loss. The best strategies were comprehensive and high-intensity (12 to 26 sessions in a year) and combined multiple approaches to help people modify behavior. These approaches included improving diet or nutrition, attending physical activity sessions, receiving group and individual counseling, setting weight-loss goals and strategizing about how to maintain lifestyle changes. Notably, the task force did not recommend using medication for weight loss because there was not enough evidence that drugs used for weight loss were safe, or that patients could maintain results after stopping the medications.

Patients who are not ready to commit to an intensive diet and exercise program can utilize less intensive options that do not rely on dangerous pills. In June 2012, The Journal of the American Medical Association published a study showing that meaningful weight loss can be achieved by starting with less expensive and less time-consuming options and later adding on more services if weight-loss goals have not been met. The less expensive program in the study included monthly group counseling sessions teaching a program of diet and exercise, combined with written educational materials and a home diary. If these measures failed, patients were offered additional diet-and-exercise counseling and meal-replacement shakes or bars. This stepped-care approach produced clinically meaningful weight loss (an average of 7 percent of body weight) and was much more affordable than strategies that started patients out with more services and tapered down over time (although participants who started out with more services did lose a little more weight on average).

Diet and exercise interventions can work even in challenging settings. A randomized, controlled study published in the journal Pediatrics in 2011 proved that sustained weight loss was possible for overweight (having a body mass index higher than 95 percent of their peers) inner-city kids from ethnically diverse backgrounds. The successful program worked with children and their parents and offered nutrition classes, behavior modification therapy and exercise sessions. The children in this intensive program lost significantly more weight than those children who simply attended two diet-and-exercise counseling sessions, and the difference remained significant even a year after the program had ended.

Applying common sense

Researchers are unlikely to ever find that magic pill that makes weight loss easy and safe. It is time to turn away from decades of failed research, billions of wasted dollars and countless avoidable injuries caused in the search for an effective diet pill. As often happens, the best medicine applies what we have understood for years: eating less and exercising more are the keys to healthy weight loss.