“Tapas is Proper Diet, Mantra Chanting and Self-Inquiry.”
– T Krishnamacharya commentary on Bhagavad Gītā Chapter Six verse 46

“Everything we see,
including the instrument of mind,
has three qualities or natures.
All matter has the three qualities.
In Saṃskṛta they are known as Guṇa.
In Sāṃkhya it is said that every problem
comes from the Guṇa and their interplay.
The effects can be based on what we see, eat, hear,
and the effects of what we see, eat, hear.
In Yoga one who has mastered themselves is one
who can produce whatever Guṇa is required.”
– TKV Desikachar on Sāṃkhya and Yoga

“Regarding Yama and Niyama, these days, he believes, they have no validity except for two of them.
First, what is called Satya Niyama, or what to speak, what not to speak, to whom to speak, how to write, what not to write. These are Satya Niyama.
Another Niyama that should be followed is Āhāra Niyama. That is, how much to eat and what to eat, according to age, profession, etc. You see, the ancient people believed that a young boy could eat as much as he liked. But a Saṃnyāsi should only eat eight handfuls of rice, no more, per day.”
– TKV Desikachar from lectures on ‘The Yoga of T Krishnamacharya’, given at Zinal, Switzerland 1981.

“In Āyurveda, it gives certain behaviour by which we can stay well.
If a person follows the following he will freer of sickness.
Regularly, systematically he eats, rests and exercises adequately.
Both in amount and quality.
Food or Āhāra, along with Vihāra – recreation, rest, exercise, other activities.”
– TKV Desikachar France 1983

“Our relationship with Food can be too little, too much, or wrong.
According to Āyurveda, even the best food eaten in the wrong amount,
or at the wrong time, or with the wrong attitude
will fail to nourish and even disturb the system.
The same could be said for Yoga Practice.”