Bhagavad-gita never says that "you don't require to eat. You simply breathe air and practice yoga." No. But we must eat neither more, nor less. That is recommended. Yuktahara-viharasya. We should not eat more, nor less. And nirasih. Nirasih means desireless of extravagance. Now we are desiring for sense gratification more and more. That is not wanted. If you want perfection of life... This is called tapasya.
Lecture on Bhagavad-gita 4.21, Bombay, 10 April, 1974