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Is Fasting Healthy?

Fasting has been practiced for centuries. But can it really help you lose weight and get healthier?

Fasting to Treat Disease continued...

In his practice, Fuhrman tells WebMD, he has seen fasting -- combined with improving the diet before and afterward -- eliminate lupus, arthritis and chronic skin conditions like psoriasis and eczema. He says he has also seen fasting heal the digestive tracts of those with ulcerative colitis and Crohn's disease, and lower blood pressure.

"Fasting followed by a vegetarian diet interferes with the immune system's activities, especially if the immune system is overreacting, as it does with ," and other auto-immune diseases, he says. He cites half a dozen studies published in medical journals ranging from the American Journal of Physiology - Endocrinology and Metabolism to the Scandinavian Journal of Rheumatology.

Studies published in The Proceedings of the National Academy of Sciences and The Journal of Nutrition in 2003 showed that mice forced to fast every other day, while eating twice the normal amount of food on non-fasting days, had better insulin control, neuronal resistance to injury, and other health indicators than mice fed calorie-restricted diets.

Fasting may yield psychological benefits as well.

"I use very brief fasting with my patients to help them cope with stress and depression," says Agnese Barolo, a life coach in contemplative practices in New Rochelle, N.Y. "I start them with just a few hours – so they learn to say no to food. It’s the first step in taking control of their lives."

Many are so encouraged that they try longer fasts, she says.

"I know some doctors say there is no scientific evidence for the curative powers of fasting," Barolo says. "But there is a reason every culture in every country has practiced some form of fasting for thousands of years." 

Fasting is not advisable for everyone. But for those whose medical conditions do not respond to other treatments, Fuhrman says, "sometimes fasting four to five days a month can help them break to a next level of immune competency."

He adds that "it will only work if you frame the fast with good nutrition before and after. For most medical conditions, if you stick to a strict diet, you don’t even need fasting."

Fuhrman cautions that certain people should not fast, including:

  • Pregnant women.
  • People with wasting diseases or malnutrition.
  • Those with a history of cardiac arrhythmias.
  • People with hepatic or renal insufficiency.

And anyone who fasts for extended periods should do so only under close medical supervision.

Fasting for Longer Life

"There are hundreds of studies showing that when animals are fed fewer calories they live longer," says Fuhrman.

Studies on animals ranging from earthworms to monkeys have shown that alternating cycles of fasting and very calorie-restricted diets is a reliable way to extend the lifespan.

"The excess calories Americans eat shorten their lives," says Fuhrman.

If you want to live longer, Fuhrman's best advice is to "eat healthy and fast periodically."

The time may come," Fuhrman says, "when not offering this substantially more effective nutritional approach will be considered malpractice."

Reviewed on February 01, 2007

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