Fasting (Not eating anything for a day) is an integral part of Hinduism, Buddhism and Islam. Although, these religions suggest fasting to cleanse the soul; Fasting has other benefits for body as well. The benefit to body is both direct and indirect.
Direct benefit of fasting is that it relaxes the digestive system of the body and allows the body to regulate its metabolism (in simple it’s the rate at which body burns glucose to release energy).
Indirect benefit, which in some ways is much bigger than the direct benefit, is that it turns the faster’s attention away from things he or she loves to indulge in. One such common indulgence is food.
As it’s not easy for some people to turn their attention away from material things (food that tastes good included) not even while fasting; that’s why those religions who tell people to fast, also advise them to focus on God while fasting. This acts as an anchor for the wandering mind. Hence the prescription of religions to concentrate on God during fasting is not just to make people fast; but it has scientific reasoning to it as well.
A weekly fast is a good thing.
But it’s important to note that:
1) The one meal, usually taken at the end of the fasting day, should be as simple and light as possible. The quantity of meal should be less as well(about 30 percent less than one takes on non-fasting days).
2) It’s not good to pre plan or plan all through the fasting day, the meal one will take at the end of the day. This defeats the indirect purpose of fasting– which is to effect more deep and long term changes in body and lifestyle. So while fasting, no matter how much your mind wants to think about food, try to stop it by using the anchor– which is God.