With the number of obese Americans on the rise and the numbers of the merely overweight growing, there is growing concern about the number of individuals who have chosen fasting as a way to keep their weight down. Fasting restricts caloric intake and can help one lose weight, but is it a safe method of dieting?

To make matters even more complicated, there is a new and disturbing trend among dieters, called intermittent fasting.

Intermittent fasting is a radical approach to weight control wherein the dieter just doesn’t eat on certain days or certain times of the day. Instead of trying to control temptation in restaurants or grocery stores, the dieter eats all he or she wants and then doesn’t eat at all at particular times of day or on pre-chosen days.

Scientific research seems to support fasting as a method of weight control, not to mention that it is a regular practice of many religions and cultures around the globe. The practice seems to make the dieter more circumspect about the food one partakes in and can also yield the benefits of calorie restriction, which may ultimately reduce the risk of some diseases and even extend life. In some case intermittent fasters may switch from rarely depriving themselves to a normal regiment of depravation.

Researchers say that in normal healthy subjects, moderate fasting (maybe one day a week or cutting back on calories a couple of days a week) will have health benefits for most people. This belief is not supported by all researchers, however. Some research has shown that dieters who fast one day a week take in more calories than normal on their non-fasting days.

Advocates of fasting say that from a biological standpoint, fasting can be helpful whether someone is overweight or of normal weight. Fasting and calorie restriction will lead to an adjustment of ones body, and in about three weeks the body hunger cycle will ultimately adjust to the new routine. During fasting, almost every system in the body is turned down. The body changes how it uses “fuel” and certain hormone levels fall drastically. Growth also stops and reproduction becomes impossible, as unnecessary body functions are ignored.

Researchers aren’t exactly sure why the body apparently benefits from a state of mini-starvation, but here are several theories. One is that the process produces just enough stress in cells to be good. The mild stress stimulates the production of proteins that protect the neurons against more sever stress. Scientists believe occasionally going without food also makes the body more sensitive to insulin, which helps maintain regular blood sugar levels.