Srimad-Bhagavatam: Canto 3 - Chapter 1 - Verse 60

Sanskrit:

क्षुत्पिपासे तत: स्यातां समुद्रस्त्वेतयोरभूत् ।अथास्य हृदयं भिन्नं हृदयान्मन उत्थितम् ॥ ६० ॥

ITRANS:

kṣut-pipāse tataḥ syātāṁsamudras tv etayor abhūtathāsya hṛdayaṁ bhinnaṁhṛdayān mana utthitam

Translation:

Next grew feelings of hunger and thirst, and in their wake came the manifestation of the oceans. Then a heart became manifest, and in the wake of the heart the mind appeared.

Purport:

The ocean is considered to be the presiding deity of the abdomen, where the feelings of hunger and thirst originate. When there is an irregularity in hunger and thirst, one is advised, according to Āyurvedic treatment, to take a bath in the ocean.