10/02/2010 11:01 am ET | Updated Nov 17, 2011

Weight Loss Drugs: 'First Responders' in a Diet Program

A few days ago, an advisory panel to the FDA rejected approval of a new weight loss drug, Lorcaserin. The main reason for rejection was concern that it might cause cancer. Rat studies in which relatively high doses of the drug were tested had produced tumors. But it seems that the second reason for rejecting the drug is that it simply didn't work very well.

Weight loss drugs should cause weight loss. And Lorcaserin did, but in such small amounts that the drug's effectiveness barely met FDA standards. After a year, volunteers taking the drug lost only about 5.8 percent of their original body weight. As comparison, the people on placebo did even less well. They lost about 2.5 percent of their body weight.

If you only had 20 pounds to lose, 5.8 percent of your starting weight might be acceptable. For example, if you were a woman weighing 140 pounds whose goal weight was 125 pounds, taking the drug for a year would allow you to lose about 8 pounds. And if those eight pounds motivated you to continue losing weight after you no longer were on the drug, then taking it would have been very helpful. However, eight pounds over 12 months is a very small amount of weight to lose, especially since the volunteers were all put on a diet and exercise program. If you had considerably more weight to lose, then you might get frustrated at how slowly you were losing it and stop the drug or the diet. So it is understandable that the weight loss results were not substantial enough to win approval.

Meridia, a diet drug that has been sold for several years, has also been scrutinized recently because of concern over its side effects and weight loss effectiveness. Sibutramine (the chemical name of Meridia) was the focus of a large study looking at deaths from its use. The SCOUT trial (sibutramine cardiovascular outcomes trial) put almost 11,000 people on the drug for six weeks and they lost, on average, 2.6 kilograms or slightly less than six pounds. Then, for the next three-plus years, the volunteers either continued to receive the drug or a placebo. The drug group lost about four more pounds over three years. This means that their total weight loss for about three and half years was the grand total of about 10 pounds.

People in the study were chosen because their health would have benefited from weight loss, i.e. they all suffered from cardiovascular disease, type-2 diabetes, or both. Unfortunately, neither their weight nor their health benefited from treatment with Meridia as the incidence of stroke, heart attacks and death were higher among those getting the drug.

So here are two weight loss drugs producing micro amounts of weight loss with the potential to produce major side effects. Of course people get sick and may die from the effects of obesity itself. In all fairness one could say that any weight loss may be beneficial. But the slow rate of weight loss among people on both of these drugs indicates that not only were people not eating substantially less (otherwise they would have lost more weight), they must not have accepted the other lifestyle changes that promote and maintain weight loss

No drug, by itself, can bring about the changes supporting permanent weight loss such as increasing physical activity, removing triggers to emotional overeating and changing eating to a way of getting nourished rather than as a substitute for recreation and loneliness.

Weight loss drugs should be considered "first responders" that come to the aid of the dieter when the diet program begins. By immediately decreasing food intake, the drug gives the dieter the sense that she is finally in control of her eating. Because she is no longer struggling every minute with whether or not she should be eating some forbidden food, she has the breathing room to develop a healthier eating style, to begin an exercise program and to identify triggers to emotional overeating and find activities that will replace chronic snacking.

The dieter has to understand that there is no "magic pill" that can bring about all these changes. A weight loss drug is like a fireman who responds to a fire. The drug may dampen the flames of overeating but only the dieter can rebuild a healthy weight lifestyle.

What many dieters don't understand is that their own brains can help them do this, without diet drugs. Their brains contain a neurotransmitter, serotonin, which, when properly activated, stops emotional overeating, increases energy so that exercise becomes possible and makes the eater feel full after only moderate amounts of food. Serotonin is made after carbohydrates are eaten and digested. All carbohydrates except the sugar in fruit have the ability to stimulate serotonin production. The best carbohydrates however, are those with the least processing such as brown rice, whole grain breads, cereals and pasta because they will provide important nutrients as well. As long as they are eaten with very little protein ( protein prevents serotonin from being made) and very little fat (fat slows down digestion as well as weight loss) , serotonin will made.

Carbohydrates are, in a sense, a first responder. By turning down the appetite, the dieter has time to consider what to eat, how much, and when. But even serotonin can't fill up a long Sunday afternoon with activities, shorten a toxic commute or turn the boss from hell into a pussy cat. It's up to the dieter to create a lifestyle that supports, and maintains, weight loss.