I just finished the longest fast I have ever completed. It's not really fair to call it a "fast", since I did eat brown rice twice during the 48 hours, but it was a detox fast. The experience was more eye-opening than I had imagined and although I felt a bit "out of it" for most of the weekend, I did end up with a much higher appreciation for food.
I'm considering starting a monthly weekend-detox to regularly clean my system. Since I'm vegan, you may wonder what toxins I could be cleaning out. Well, there are a lot more toxins in our bodies than you might imagine -- even toxins unrelated to food! An article titled "How Toxins Affect Your Energy Health" has a nice explanation:
It is nearly impossible to free your body of toxins because they are everywhere. Toxins can be found in the air you breathe, the food you eat, and your body can even create toxins from too much stress. Even if you can not get rid of all the toxins in your body, it is still important to reduce the level of toxins so your health and energy will not suffer. Your body is designed to handle small level of toxins on a regular basis; when there are too much toxins in your body at once, your body will start to breakdown and you may suffer from health problems, such as headaches, fatigue, nausea, sickness and chronic diseases.
Fasting is one of the many ways we can clean toxins out of our body. A detoxification fast usually consists of eating a single simple food that is easy to digest, such as brown or white basmati rice, and nothing else for several days at a time (of course you must drink water to stay hydrated!).
Calorie restriction has been shown to improve overall health and slow the aging process. The low-calorie Okinawa diet, for example, is thought to be a direct reason why a high proportion of Okinawans live to over 110 years of age.