The wackiest diet that Melissa Payne has ever heard of would probably be "God's diet."

"God's diet was pretty radical and the philosophy behind it is that if God didn't make it, you should not eat it," says Payne MS, RD, LDN, at Orlando Regional Health Care in Orlando, Fla. "It involved huge lists of things you could and could not eat and there were a lot of restrictions in terms of sucrose, fructose, glucose, and all sugars," she recalls.

Other nutty ones that Payne and her colleagues who are on the front lines of our diet-obsessed society have heard about include the all-peanut butter diet, the breathing diet, the cabbage soup diet, the raw-food only diet, and the blood type diet.

Just stroll down the diet/health section at your local bookstore and you are likely to be bombarded with diet books, many with doctors' or celebrities' names attached. There's actress Suzanne Somer's, Get Skinny on Fabulous Food, The Metabolic Typing Diet, which comprises self-tests to discover your own metabolic type and determine what kind of diet will work best for you, and Dr. Kushner's Personality Type Diet, which looks at diet, exercise pattern, and any emotional barriers that keep you from your ideal weight.

And there's more: The Eat Right 4 Your Type: Blood Type Diet suggests different diets for different blood types because foods are metabolized in a unique manner by each blood group. And there seems to be a new breathing diet every few years. The premise is if you increase the amount of oxygen to various parts of your body, it works more efficiently, your metabolism speeds up, and you lose weight.

"The cabbage soup diet was big and so were 'combination' diets where you can't have fruit with any other food group and meat and starches can't be eaten together and the liquid-cleansing diets," Payne says.

"People want a quick fix and they also want a program to follow," she says. "It's not enough to say watch portion sizes and increase exercise, they need more structure."

The Lure of the Fad Diet 

Fad diets promise structure and immediate results. "And sometimes the better the packaging, the more the appeal," Payne says."The South Beach diet is more glamorous than following the USDA food guide pyramid."

What's more, "people are so confused by nutrition and are not sure who to believe," she says. "A lot of the ads sound promising and easy to buy into because most say you can eat all you want, not exercise, and lose all the weight," she says. "We don't think about long-term health benefits."

That's for sure, says Joy Short, an assistant professor of nutrition and dietetics at St. Louis University in St. Louis.

Short says that by far "the most popular fad diet is the current low-carb craze, but I have seen everything under the sun from earrings that rev up metabolism to drinks that zap fat out of the intestinal system."

Craze? The popularity of low-carb diets is more like a revolution!

In fact, 20% of adults said they had tried a low-carb diet since 2002 and 11% of Americans (or 24 million adults) are currently on one, whether it be Atkins or another plan. And 19% of people who are not currently on a low-carb diet are "very" or "somewhat" likely to try one in the next two years, according to a survey of 1,800 U.S. adults by Opinion Dynamics Corporation in Cambridge, Mass.

Anatomy of a Fad Diet

Generally fad diets "take something that has been shown through a little research to be beneficial like peanut butter (which is rich in "good" monounsaturated fat and protein and helps you stay full) and then someone recommends it at every meal throughout the day," Short says.

"We want something and we want it now," she says. "Moderation, variety and balance in the diet takes effort, long-term commitment and lifetime change and people aren't patient."

In addition, fad diets are very specific, which people find appealing. "It's so cut and dry, giving you something to follow that you see as a recipe for success and think it might work," Short says.

Finally, Short says, most fad diets are sold through "it worked for me" testimonials, which consumers love and the research community hates.

Fast-result, fad diets provide people with instant gratification, Goody tells WebMD.

However, they don't promote proper maintenance of the weight that has been lost. Most of the popular diets are nutritionally inadequate and include certain foods that people would not typically eat in large amounts.

So how can you detect one of those "crazy diet fads"?

"If it promises a quick fix, is simple, lists good and bad foods, makes dramatic statements, and has no scientific basis, then it's too good to be true," Goody says. "There are no good foods or bad foods," she says. "It's all about portion control and downsizing over supersizing."

Whether it's grapefruit, cabbage soup, or peanut butter, "a single nutrient diet can't give you all the vitamins, nutrients, protein, carbohydrates, fat, and water that your body needs," she says.

Summing It all Up

"People like to eat and losing weight is tough," says Jeanne Goldberg, Phd, RD, a professor of nutrition at the Friedman school of nutrition science and policy at Tufts University in Boston.

"It's really hard to cut back on calories and increase physical activity sufficiently such that you follow a very moderate path step by step until you have lost the weight that you want," she says. "All of these diets promise a quick fix, but you don't get fat overnight or over two weeks and you don't get skinny in that time frame either," Goldberg says. "All of these diets are magic bullets that claim to defy the laws of energy balance which is calories in must equal calories out."

"It's really hard to say 'this will happen to you if you follow this diet' and the truth is that there is some evidence that people have lost weight on every diet that you conceive of, but the trick is can they keep the weight off?"

And with fad diets, the answer is a resounding no!

Published Feb. 25, 2004.

SOURCES: Melissa Payne, MS, RD, LDN, Orlando Regional Health Care, Orlando, Fla. Joy short, assistant professor, nutrition and dietetics, St. Louis University in St. Louis. Cynthia M. Goody, PhD, RD, LD, University of Cincinnati Medical Center, Ohio. Jeanne Goldberg, Phd, RD, professor, nutrition, Friedman school of nutrition science and policy at Tufts University, Boston.