Of the two, Prana and Vasanas, the Yoga student can regulate Prana by moderate eating (Mitahara), Yogic postures (Asanas), and Shakti-Chalana.

Gautama, o Gautama! I'll clarify the differences between all three fields. With rapt attention, listen.

The Yogi should eat foods that are sweet and healthy. He should eat enough to fill half of his stomach. One fourth of his stomach should be filled with water. 

In order to appease Lord Siva, the Yogins' patron, he should leave the fourth quarter of his stomach empty. This is a good example of dietary moderation.

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