Fasting is used by many as a way to detoxify and rid the body of built-up waste. A fast can be rigorous, allowing nothing but water, or it can be less onerous, with fruit juices and herbal teas considered acceptable. Individual responses to a fast will vary and will depend on the type and length of the fast. Individuals suffering from illnesses such as cancer, AIDS and any potentially fatal disease should avoid fasting, as should pregnant women and infants. Fasting for diabetics is not advised, but should you decide to do so, you should only fast under medical supervision.
According to the Natural News website, your body will need three days to stop craving food, so you will be hungry during your fast. Some people suffer few side effects, while others may experience headaches and muscle pains as the body strives to accommodate the metabolic changes resulting from decreased nutritional input. Your pre-fast level of toxicity may contribute to the side effects, which could also include bad breath, blemishes and unpleasant body odor as toxins are released. Be prepared to get additional rest, since your energy stores will be low and you initially may feel fatigued.
Fasting, Cholesterol and Fats
One of the body's responses to fasting has been reported by researchers from Harvard University. According to this study, when you fast, one of the sirtuin enzymes in your body, which they called SRT1, shuts off the proteins involved in fat and cholesterol production. Fasting causes your body to stop making and storing fat and cholesterol, and instead, starts using the fat you have already stored as a source of energy.
Fasting and Human Growth Hormone
As reported in ScienceDaily, cardiologists at the Heart Institute of the Intermountain Medical Center in Murray, Utah, conducted a research study that examined the effect of fasting on levels of human growth hormone, or HGH. HGH is involved in maintaining metabolic balance and providing protection to the body's lean muscles. A 24-hour fast caused an average increase in HGH levels in females of 1,300 percent, while an increase of 2,000 percent was seen in males.
Long periods of fasting can cause severe reactions such as decreased blood pressure, anemia, mineral imbalance and compromised liver function. While the hunger associated with a fast will eventually go away, your body still has to deal with the stress of the fast, and a long-term fast could be dangerous to your health.