Drinking Yourself Skinny

When Lynette Sylvester weighed 259 lbs., she hated Jane Fonda. The movie star was everything that Sylvester, 42, wanted to be and wasn't: among other things, svelte and athletic. In fact, Sylvester's weight problem had become so severe that her physician recommended she have her stomach stapled. "I realized that if I didn't change my behavior, I would die," recalls the store owner from Burnsville, Minn. Determined, she went on a liquid-protein diet and lost 120 lbs. Now, a year later, down from a size 44 dress to size 10, Sylvester regards Fonda as her personal exercise guru.

Liquid diets, which enjoyed a burst of popularity in the 1970s, are once again a fad. Programs are being offered in thousands of clinics, hospitals and doctors' offices across the country. Advertisements and articles tout the diets' merits. Celebrity success stories like that of TV talk-show host Oprah Winfrey, who shed 67 lbs., heighten the interest. In all, the liquid regimens have grown into a $100 million-a-year industry. But the re-emergence of the diets has raised questions about their safety and long-term effectiveness.

The dominant firms in the field, all national chains, are Health Management Resources, Medifast and Optifast (which directed Winfrey's loss). Their programs are similar. Patients are put on so-called VLCDs -- very-low-calorie diets -- requiring them to forsake solid food and drink five packets a day of flavored powdered-food supplement containing a total of 400 to 800 calories. Dieters visit the program's doctor and a behavior-modification class once a week to have their health monitored and learn new eating habits. The average weight losses are dramatic: 3 lbs. a week for women and 5 lbs. for men. The fasting phase of the diet, which generally lasts from three to six months, is pricey: about $100 a week (part of which may be reimbursed by medical insurance). After hitting their goals, patients go on less expensive maintenance programs, designed to help them fend off cravings to overeat.

Are the programs safe? Yes, say experts, if they are medically supervised and if there is a significant amount of weight to be lost. That rules out the casual dieter, who risks poor health by losing muscle tissue. "These programs are definitely not for a patient who has 20 lbs. to lose and wants to get into a bikini," says Jim Parsons, Optifast's director. Nor are they for the do-it- yourselfer. "If you use an over-the-counter formula product as your sole source of nutrition, it's like playing Russian roulette," says Joan Horbiak, spokeswoman for the American Dietetic Association. Patients in liquid-diet programs occasionally suffer temporary side effects, such as fatigue, constipation, dizziness and hair loss.

Apprehension about liquid diets stems from the more than a dozen deaths caused by such regimens a decade ago. At that time, the unsupervised diets contained only 300 calories a day and were made of nutritionally deficient hydrolyzed gelatin. Since then, calorie levels have been raised and the products improved. "Now programs invariably use high-quality protein," says Victor Frattali, a nutritionist at the U.S. Food and Drug Administration.