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Fasting: Harmful Or Helpful?

Dieters looking for a quick fix that will enable them to clean out their systems and lose weight have long turned to lengthy juice or water fasts to do the trick. But Health magazine reports that long-term fasting can actually cause more harm than good.

For the May issue of Health, Samantha Heller, a registered dietician and contributor, researched the various kinds of fasts and diets that promise to remove toxins and claim they can leave dieters looking and feeling better. However, she was unimpressed with the science behind the fasts and the results they offered.

Detoxification, she pointed out in the magazine, is something that our bodies do naturally every day — regardless of whether we are eating normally or restricting ourselves to liquids.

According to Heller, there are a few advantages to going on a very short-term juice or water fast — dieters can break a cycle of binging; it can make a dieter more aware of what he or she is eating every day; and it may even encourage dieters to add more fruits and vegetables to their meals.

However, when done over several days, a fast can also be harmful. Heller outlines some reasons:

  • An extreme cutback in calories for more than a day or two scares the body and sends it into survival mode. The body will work to conserve energy and slow down metabolism.
  • In most cases, the lost weight is just water weight that will be regained after the detox program has ended.
  • Some detox diets include herbal supplements that could contain laxatives. Dieters may feel lighter but they haven't lost fat. Overuse of laxatives can lead to dehydration and other medical problems.
  • While some fasters claim to experience a feeling of euphoria, the feeling may be due to the fact that they've stopped eating a lot of unhealthy food or feel good that they have lost some weight and gotten control of their eating. They could even be experiencing the light-headedness associated with low blood sugar.
  • Fasting while taking certain medications can be dangerous, and it's certainly not advisable to go off prescribed medications without first talking to your physician.

    Heller had some helpful tips for anyone who is considering doing some extreme bodily spring cleaning:

  • Dump junk food and fast food.
  • Eat vegetables (any kind) at least two times a day.
  • Have one or two fresh whole fruits every day.
  • Choose only lean and low fat sources of protein, such as fish and chicken. Go organic if you can find it and can afford it.
  • Try to buy organic produce from local farmers, if available.
  • Drink plenty of fluids, including water, teas and seltzers.
  • Include unsalted nuts several times a week.
  • Add more fiber to your diet by adding beans (kidney, chick pea, white beans, split peas etc.) to salads, soups and pasta dishes.
  • Choose whole wheat, oats and whole grains nine times out of 10. Examples: whole wheat bread, whole grain pasta, oatmeal and multigrain cereals.
  • Add walnuts, avocado, tofu, edamame (green soybeans) and canola oil to your meals several times a week.
  • Limit alcohol intake.

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