Can periodic dietary cleansing make you healthier?

Can periodic dietary cleansing make you healthier?

January is a time when many people are looking to undo the damage caused by weeks of holiday indulgence. For some, a so-called "detoxification diet" seems like a perfect solution. The term "detox diet" is applied to a range of eating plans, from two-day juice fasts and short spans of consuming only vegetables and water to radical regimes that include colonic irrigations (a procedure similar to an enema). Advocates say periodic dietary cleansing helps clear toxins (originating, they claim, from pollution and junk food) that accumulate in the body's fat stores and can result in headaches, fatigue and increased risk for chronic diseases, such as cancer.

Supporting evidence: "For a week or so, fasting or following a very restrictive diet generally isn't a problem," says David Grotto, R.D., a spokesperson for the American Dietetic Association. "And many people say they feel better after doing it." Still, says Grotto, there isn't any scientific evidence to back the benefits ascribed to detoxifying eating plans.

Pros: "Many programs encourage eating lots of fruits and vegetables, which are high in water and fiber and may help move things smoothly through the GI tract, and this tends to make people feel better," says Grotto. Taking a temporary break from caffeine, alcohol and refined sugars—as is prescribed by most of these plans—may not only eliminate energy crashes sometimes associated with these ingredients but also could help people realize just how much "junk" they normally consume, says Dawn Jackson Blatner, R.D., at Northwestern Memorial Hospital Wellness Institute in Chicago. In this way, detox periods may inspire longer-term healthy changes.

Cons: Colonic irrigations done improperly can seriously injure the large intestine, so avoid them, says Grotto. Even "safer" plans (those that promote eating only select, nutritious foods) may cause fatigue or dizziness if they don't supply adequate calories. If severe calorie restriction is sustained for more than a few days, the body may sense impending starvation and release stress hormones that cause fat stores to break down rapidly-a response that, ironically, may increase circulating toxins. "When fat is metabolized very quickly, the process may free up toxins at a rate that overwhelms the body's capacity for dealing with them," says Peter Pressman, M.D., an internal-medicine specialist at Cedars—Sinai Medical Center in Los Angeles. Finally, the enhanced energy that detox dieters often report may be the result of surging stress hormones too. (Evolutionarily, it makes sense: a "fight or flight" response drives hungry animals to seek out food aggressively.) An adrenaline-charged drive is short-lived, and with prolonged calorie restriction, the body powers down to conserve energy, ultimately slowing the metabolism.

Our Verdict: If you're a healthy adult, living on vegetables and water for a few days isn't likely to do you harm—or much good. "People who operate on the mode of ‘live today, detox tomorrow' are fooling themselves," says Grotto. Optimizing your body's natural detoxification systems, he says, is best achieved by consistently practicing healthy behaviors: consuming nutrient-rich foods, drinking plenty of fluids, getting adequate sleep and exercising regularly.

January/February 2007