The duration of fasting usually depends on the age of the person undertaking a fast. The nature of disease also plays a role in determining the period of fasting. Long duration of fasting should only be undertaken under professional guidance.

Occasional fasting is highly helpful for eliminating toxic wastes from the body. Short fasting is ideal for treating stomach and intestinal disorders. Fasting is harmful for people suffering from diabetes and tuberculosis.

A person can also undergo fasting when the person feels that he/she has had more than enough food or when there is a loss of appetite. After heavy meal, it is good to fast for a couple of hours or to avoid the next meal. While undertaking a fast, having fruit juices is highly beneficial as it fastens the elimination process.

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