Śivasaṃhitā 3.43

The text introduces here a rule of synchronization between the nasal breathing cycle and the act of eating. When piṅgalā — the solar channel, the right nostril — dominates breath flow, the digestive fire (agni) is at its optimal point. Eating at that moment ensures complete transformation of food into ojas and dhātu, without toxic residues. It is yogic chronobiology applied to daily nutrition.

Anila’rkapraveśa (entry of air into the sun) designates the moment when prāṇa circulates predominantly through piṅgalā nāḍī, the solar channel associated with heat, action, and digestion. The instruction sadā (always) is not hyperbole: the yogin must develop sufficient sensitivity to detect which nostril dominates at each moment and adjust their daily schedule accordingly.

The promise that prāṇāyāma perfection reduces sleep, excrement, and urine reflects the theory of prāṇamayatā: as the yogin’s body becomes more subtle, its metabolism becomes more efficient, requiring less elimination of residues. Later masters of the Theosophical tradition and the modern yoga movement interpreted this literally; contemporary physiological studies confirm that conscious breathing effectively affects metabolic cycles.