If you're looking for a way to lose weight quickly and feel better (and who isn't?), you might be tempted to try a fad "detox" diet or a "cleanse" method." These diets start with a fast, followed by a period of consuming only raw vegetables, fruit, juices and water.

Most nutritionists say, "Don't bother."

There is no scientific evidence that "detox" (short for detoxification) or "cleanse" diets result in rapid weight loss or have any health benefits, says Heather Mangieri, RDN, LDN, a spokeswoman for the Academy of Nutrition and Dietetics and founder of Nutrition CheckUp in Pittsburgh.

Indeed, the opposite may be true: One study published in 2011 in the journal Obesity found that beginning a weight-loss diet with a fast or cleanse could be counterproductive.

For example, researchers at the University of Illinois divided mice into two diet groups. For 10 to 12 weeks, one group of mice was fed a low-fat diet (10 percent fat). The other group was fed a high-fat diet (60 percent fat). Not surprisingly, the group on a high-fat diet gained a lot of weight. Afterward, both groups were put on a 24-hour fast. The lean mice lost 18 percent of their body weight in those 24 hours, but the obese mice lost only 5 percent.

Cleansing diets aren't new. "They've been around for years and years," Mangieri says. But they seem to get a lot of press from magazines and talk show hosts. And celebrities make cleanse diets popular every time they claim to lose significant weight on them.

"The terms 'detox' and 'cleanse' have become almost interchangeable and are thrown around almost as much as the words 'calorie' and 'carbohydrate' these days," says Keri Glassman, RD, CDN, founder and president of A Nutritious Life, a nutrition practice based in New York City.

Proponents of cleansing diets believe it's important to rid your body of toxins that you get -- like it or not -- from food, water and the environment. "The mistake most people make is equating detoxes and cleanses with weight loss," Glassman says. They are not the same.

So if you're considering a cleanse diet as a way to lose weight, you could be outsmarting yourself. "Cleanse diets can set you up for failure by slowing your metabolism and making you crave everything you just gave up," Glassman says. Cleanse diets don't help you or your body develop healthy eating habits. And what's worse, they could deprive your body of essential nutrients, Mangieri agrees.

Glassman says it's not necessary to go on a special diet to "clean" your digestive system. "Our bodies are natural systems built to detox all the time," she says. "Our liver, skin, urinary system, and gastrointestinal tract are constantly helping to cleanse our bodies through sweat, urine and feces."

Eating a diet high in fiber, drinking lots of water, and avoiding packaged and processed foods are major ways to keep your body working optimally. "Such a diet will ensure that your body is cleansing as naturally as it can," Glassman says.

Glassman never recommends that anyone go on an extreme (all liquid) cleanse diet, especially not for an extended period of time. However, she says a modified version may help you reboot your system, especially if you overindulged on vacation or have gotten into a fast-food rut.

In her book, The New You and Improved Diet, Glassman recommends a four-day regimen that some people may find helpful. It consists of eight foods:

• artichokes,
• avocados,
• eggs,
• granny smith apples,
• lentils,
• olive oil,
• salmon, and
• spinach.

"I chose these foods because as a group they offer healthy fat, protein, fiber, and water volume. Plus they're loaded with antioxidants," she says.

Glassman says eating only these foods for three or four days will help you feel better. That timeframe also can be enough to "set up new healthy behaviors," she says.

Making healthy food choices will help you feel better. "Feeling physically and mentally better will help motivate you to stick with [it] for three to four days," Glassman says. "It also may motivate you to continue to incorporate the healthy habits you learn into your daily life."