Gita Bhagavad Gita 17.7 mentions the importance of diet: आहारस्त्वपि सर्वस्य त्रिविधो भवति प्रियः। यज्ञस्तपस्तथा दानं तेषां भेदमिमं श्रृणु।।17.7।। It means - Food, which is dear to all, is of three kinds; and so also are sacrifices, austerity, and charity.