This article is from the Alternative Medicine Therapies guide.
If you'd like to try a fast of one to three days' duration, it is probably safe to do so on your own--as long as you are healthy and not pregnant or breast-feeding. If you plan to fast for longer than three days, however, you should seek medical supervision.
If your primary-care practitioner isn't willing to supervise your fast, you may want to seek a naturopathic physician, nutritionally oriented chiropractor, nutritionist, or registered dietitian. Before you begin, the practitioner should go over your medical history, conduct a physical examination, and perform other tests to be sure that your body is up to the challenge of a fast.
Prepare for your fast with a day of eating light vegetarian meals, focusing on raw fruits plus raw and steamed vegetables. Throughout your fast, drink plenty of liquids--water, if you are on a strict fast, and nonacidic juices and herbal teas, if you are on a modified fast. While you'll need to continue any prescription medicines for a specific condition, you can stop taking any nutritional supplements during the fast. The way you break your fast is also important. Ease back into solid food the same way you eased into the fast--with light meals of fruits and vegetables. A large amount of food right away may be too much for your system to comfortably handle.
At the beginning of your fast, you may feel energized. Or, your hunger may trigger headaches, dizziness, fatigue, and irritability. As time goes on, you will probably feel calmer and may even experience a heightened sense of well-being and clarity of mind. Your sleep patterns may be disrupted, however. Be sure to nap during the day if your sleep at night is lighter. In addition, your tongue may feel furry or coated, and you may develop bad breath. Rinse your mouth with plain water or water mixed with lemon juice to relieve these symptoms. If dizziness, nausea, aching limbs, or visual or hearing disturbances bother you, contact your practitioner.
Don't expect to pursue your regular activities during a fast. For a weekend fast, you will want to stay close to home. Limit exercise to walks, stretching exercises, yoga, or tai chi. Good pastimes are meditating, napping, reading, and listening to relaxing music.