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Dangers of Fasting for Weight Loss continued...

Side effects of fasting include dizziness, headaches, low blood sugar, muscle aches, weakness, and fatigue. Prolonged fasting can lead to anemia, a weakened immune system, liver and kidney problems, and irregular heartbeat. Fasting can also result in vitamin and mineral deficiencies, muscle breakdown, and diarrhea. When you drink laxative concoctions during a fast, there is an increased risk of fluid imbalance and dehydration.

The risks get more complicated and severe the longer you stay on a fast, or if you repeatedly go on fasts.

Why You Don’t Need a Detox Diet

It sounds logical that fasting could cleanse your body of harmful substances that could cause a host of ailments like obesity, fatigue, and headaches. But there is no scientific evidence that you need to fast to "cleanse" your body or remove toxins.

Your body - specifically, the kidneys, liver, lungs, colon, and skin -- is perfectly capable of removing toxins itself.

The Truth About Fasting

The bottom line: Nutrition experts agree that fasting is a potentially dangerous, and not particularly effective, way to lose weight.

Instead of a fast, opt for a healthy eating plan that you can stick with long-term Healthy diets provide a minimum of 1,200 calories and include a variety of fruits, vegetables, whole grains, low-fat dairy, lean protein, and healthy fats, along with regular physical activity.

If you are not convinced and want to go on a fast, be sure to consult your physician first.

Kathleen Zelman, MPH, RD, is director of nutrition for WebMD. Her opinions and conclusions are her own.

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