The ancient Indian seers were intelligent. They build little rituals around festivals that have a scientific reasoning. Fasting is one of them. There are many reasons to fast during Navratri. Here are a few:
#1. Purifies the mind: The benefits of fasting are not only seen on the physical level but have a positive effect on the mind and emotions as well. The body is intimately connected with the mind and the mind with the emotions. When the body is purified through fasting, the mind is also purified. The mind becomes calm, clear and peaceful.
#2. Cleanses the body: Fasting is a great therapy to cleanse the body, ridding it of toxins. One of the primary reasons for diseases is an accumulation of toxic materials in the digestive system. Fasting helps to reduce the load on the digestive system.
#3: Energize your system: Ayurveda, or the traditional Indian system of medicine, considers fasting as an effective way to rekindle the digestive fire or hunger. Fasting increases our digestive fire and this fire burns the lethargy and dullness in the body that comes through excessive eating. That is why after fasting you feel so fresh and light because every cell of our body comes alive.
#4. Adapt to change: Fasting helps the body to adapt to the changes associated with ritu sandhis(the seasonal transitions)
#5. Build self-awareness: Fasting helps a spiritual seeker to build self-control, discipline and bring more awareness to the mind.