Fasting is the process of not eating food for a specific period of time. Some religions encourage their members to fast in certain circumstances – in the Bible, Moses fasted for 40 days when he was on the mountain with God. Proponents say that a one-day fast helps to clear the mind and creates energy, a three-day fast eliminates toxins and purifies the blood, and a long-term fast promotes healing, alleviates food allergies, sheds pounds, and rebuilds the immune system. Critics believe that fasting may be unsafe for the body as it depletes important nutrients, minerals and energy, and is an ineffective weight loss aid. Few scientific studies have been done to back up health and weight-loss claims through fasting.
