In Bhagavad Gita, Lord Krishna very clearly says, "One who eats a lot will never attain yoga nor those who do not eat at all. They will also not attain yoga." That is why he said, "yuktahara-viharasya yukta-cestasya karmasu."
Krishna's way is always the middle path. He says, "Balance. A little food is essential; not too much; not too little; the right amount (yuktahara)."
Sharira Madhyam Khalu Dharma Sadhanam. This body is an instrument to attain dharma. To attain moksha. To attain the highest, you have to keep your body fit. Yoga is about this.
- Gurudev Sri Sri..