Should you go on a very-low-calorie diet?

Nation's Business, July, 1989 by Phyllis M. Barrier

Should You Go On A Very-Low-Calorie Diet? We've all heard a lot in recent months about liquid-formula diets. One of them, Optifast allowed TV star Oprah Winfrey to lose 67 pounds in just a few months.

Clinics and hospitals around the country offer many such fasting programs, on an out-patient basis. Among the names, in addition to Optifast, are Medifast, Ultra Slim-Fast, HMR, and Care Fast. Protein and calorie levels vary considerably from program to program (between 300 and 800 total calories per day, and from 33 to 70 grams of protein), as do other components. Typically, though, a patient's only food for weeks is a powdered formula dissolved in water.

More than 50 deaths were attributed to liquid-protein diets in the '70s. The liquid protein in those diets was nutritionally inadequate, but the newer very-low-calorie diets (VLCD) appear to be safe when they are administered under careful medical supervision, and they seem to be potentially effective when they are joined with behavior modification--that is, improved eating habits--and exercise.

The VLCD programs are very expensive, however, their average cost is about $2,500. The drop-out rates are high, around 50 percent. They are recommended only for severely obese people who are at least 50 pounds or 30 percent above ideal body weight. Other candidates might be those who are not quite so obese but have health problems that will respond quickly to weight loss, such as sleep apnea, high blood pressure, and diabetes.

Before VLCD programs came along, severely obese patients were treated surgically, through colon resectioning, stomach stapling, and balloon insertions--none of them successful over the long term. As far as behavior modification was concerned, doctors and nutritionists attempted to deal with very obese patients as they did patients who were only moderately obese. The idea was that gradual changes in eating habits and a slow loss of weight would reinforce each other, so that the patients would eventually wind up at their ideal weight and would eat in a way that kept them there. But Dr. Isaac Greenberg, director of the Center for Nutritional Research in Boston, says that "for people needing to lose 40 pounds or more, these [behavior-modification] diets were simply not realistic." Patients were all too likely to regain what little weight they lost.

In a carefully controlled VLCD program, however, a patient can reasonably hope not only to lose a large amount of weight but also to regain no more than one-third of the lost weight one year after completing the program.

Cindy Marquardt, a nurse in the Washington, D.C., area, who lost 100 pounds in the Optifast program, explains the power of VLCD programs: "It is very discouraging to lose a few pounds here, a few pounds there," as under most traditional weight-control programs, but "very motivating to lose more quickly. It is much easier to not eat than to eat moderately." Marquardt went through Optifast with a group of about 15 women, who gave each other moral support.

If you are thinking about entering any of the VLCD programs, you should get a thorough physical examination first, to make sure you are not suffering from conditions that might make the program risky. Dr. Harry Schumann, a Washington physician who himself has gone through one VLCD program and worked in another, says that patients with kidney problems, for instance, probably should avoid the diets because of the loss of body fluids they entail.

Different tests are recommended before entering different programs, but the tests might include an electrocardiogram, complete blood counts, and other body-chemistry tests. Some programs require that you adopt a weight-stabilizing diet or take a course in behavior modification before you start the very-low-calorie diet.

How long should you stay on a VLCD? Dr. Richard Atkinson of the Veterans Administration Medical Center in Hampton, Va., believes that "12 weeks is the maximum to insure safety." After that, there should be a gradual return to a normal diet.

Fasting brings some loss of lean body tissue and changes in metabolism as well as the loss of fat. Patients adjust to fasting psychologically as well as physically. "I felt euphoric," Schumann says. "I had a sense of well-being while I was on the fast." Weaning the patient away from the VLCD and back into a pattern of regular meals can thus difficult. Patients must deal with increased food choices for the first time in weeks, and their reactions can range from apprehension to anticipation.

The apprehension is justified. Even though very-low-calorie diets are the best vehicles now available to treat severely overweight patients, to be effective they must be only the beginning of a new lifestyle that includes radically changed eating habits, increased physical activity, and self-monitoring.