Some of the diets also rely on the notion that it's not just what you eat, but when you eat that matters. "Primitive man used to eat small meals many times a day -- find some berries here, go on, find some more there," says Moulavi, who recommends that dieters eat one of his cookies every two to three hours. "The intestine was designed for small meals throughout the day."
Turner, of the Hollywood Cookie Diet, believes cookie dieters can learn valuable eating habits. "We're teaching people to maintain calorie balance and portion control," he says.
Pacella says that happened for him. "It empowered me to learn how to portion out my day to have smaller meals," he says. "Now I can stay on the same schedule, but instead of cookies, I make smart choices, like fruit." After dieting for seven months, starting last February, Pacella has maintained his weight loss the past four months and is still using the cookies.
Nutrition experts agree that very low-calorie cookie diets, when used as directed, can make the weight evaporate. But they say research has shown that most people won't stick with a very low-calorie diet for very long.
"People go on a rapid weight loss diet and find they get tired of it and then go back to eating the way they did before," says James Hill, director of the Center for Human Nutrition at the University of Colorado Denver, nationally known for its research on obesity prevention and treatment. "The key . . . is finding a way to eat and exercise that you can do forever."
Hill also doubts that cookie diets give most people any useful practice in portion control. They're too low in calories, he says. That is, over the long term, it's unrealistic to expect people to control their portions that much.
"It is not a portion-control message, but rather a quick-fix message, that comes from these diets," Hill says.
And how do the cookies taste? Four unbiased (albeit nondieting) cookie-lovers performed an unscientific taste test of four brands of diet cookies: Dr. Siegal's Cookie Diet, Hollywood Cookie Diet, Smart for Life and Soypal Cookie Diet. None of the cookies won raves, but some were deemed not bad. Comments ranged from "Sawdust comes to mind" and "Sort of a chemical taste" to "Pretty good" and "This could pass for a regular cookie!" (See related online story for the complete taste test results.)
Cookie diet inventors have tried their products out in various settings -- on friends or patients, in diet clinics, etc. And they experimented till they were satisfied the cookies lived up to their claims.
But no one has conducted -- let alone published -- any randomized controlled trials to test these claims in a valid way. (See related story.) That's the kind of evidence scientists such as Hill and Stern crave -- to prove whether cookie diets really are a recipe for success or just another half-baked diet scheme.
A panel of taste testers tries out several cookie diet cookies. Check out their comments and details about the diets.