In medical terms, the word ‘fasting’ can be defined as “voluntary abstinence from consuming food for varying lengths of time.” Fasting is used as a therapy for several medical conditions. It is also a vital component of ritualistic and spiritual practices in many religions.

Almost all medical systems in the world acknowledge the therapeutic benefits of fasting. Ayurveda has catalogued and elaborated upon these benefits exhaustively. Fasting plays a key role in ensuring the efficacy and success of ayurveda detoxification therapy (Panchakarma treatments). Hippocrates, the father of Western medicine, believed fasting enabled the body to rejuvenate its self-healing capabilities. Many western healers have opined "fasting is the greatest remedy, the physician within." Fasting is recommended in almost all religions as a means of spiritual purification.

According to Hindu scriptures fasting helps create a harmonious relationship between the body and the soul. Hindus believe that denying physical needs is necessary for spiritual gains. Islam has given utmost importance for fasting. Muslims observe fasting during the month of Ramadan. Prophet Muhammad has explained the benefits, significance and regulations of fasting. Christians believe that fasting helps them to deepen their relationship with god. They also believe that fasting heightens their awareness of spiritual self. Jain religion strongly emphasizes on fasting to purify our souls, improve morality, spiritual power, increase knowledge and strengthen relationships Paryushan Parva is a jain fasting festival which is observed in month of September.

According to researchers the following changes take place in our body when we fast:

• The body uses glycogen reserves (stored sugar to help energy supply).
• Major detoxification process starts.
• Number of white blood cells increase.
• Immunity gets boosted.
• Inflammation of inner layers of digestive system decreases.
• Some muscle loss occurs during fasting.
• Liver converts stored fats and non-essential tissues into ketones to fulfill the supply of energy to brain and heart. The process is called as ketosis. This stage is reached on third day of fasting in men and second day of fasting in women. At this stage the sensation of hunger vanishes and many people experience increased energy level at this stage.
• Between the fourth and seventh day of fasting, hormonal levels are balanced, excess fat and damaged tissues are burnt and clarity of mind is experienced.

Ayurveda recommends regular, short-term fasting. Infrequent long term fasting vitiates doshas and may lead to imbalanced body functions. The fasting method must be decided according body constitution. The duration of fasting and type of fasting is determined after analyzing level of toxin (ama) accumulation, digestive strength, vitiation of doshas and body constitution. The following fasting methods are recommended in ayurveda.

• Consuming light foods like gruel, kitchari or kanjee.
• Fasting with fruit juice or vegetable juices
• Drinking only warm water or herbal teas.

A healthy fasting leads to a feeling of lightness in the body, clarity in the mind, and increased energy. It helps to regularize bowel movement and relieve constipation. Clean tongue and fresh breath indicate completion of detoxification process during fasting. It is very important to stay calm during fasting. Texts of Ayurveda strictly recommend avoiding physical exertion and mental stress during fasting.

• Acne, pimples and other skin conditions like eczema, psoriasis clears up faster when a person fasts.
• Fasting reduces joint pains in conditions like rheumatoid arthritis and gout.
• It helps to overcome addictions and help in deaddiction.
• Fasting brings glow to skin and makes skin radiant.
• Body energy level and Immunity increases when you fast.
• Body tissues get rejuvenated.
• Helps in weight reduction and to control obesity.