Maitri (Maitrāyaṇīya) Upaniṣad 6.13

6.13

athānyatrāpi uktam viśvabhṛdvai nāmaiṣā tanurbhagavato viṣṇoryadidamannaṃ prāṇo vā annasya raso manaḥ prāṇasya vijñānaṃ manasa ānandaṃ vijñānasyeti annavān prāṇavān manaśvān vijñānavān ānandavān ca bhavati yo haivaṃ veda yāvāntīha vai bhūtānyannamadanti tāvatsvantastho'nnamatti yo haivaṃveda |
annameva vijarannamannaṃ saṃvananaṃ smṛtam | annaṃ paśūnāṃ prāṇo'nnaṃ jyeṣṭhamannaṃ bhiṣak smṛtam ||

13. Now, it has elsewhere been said: ‘That form of the blessed Vishṇu which is called the All-supporting—that, verily, is the same as food. Verily, life (prāṇa) is the essence of food; mind, of life; understanding (vijñāna), of mind; bliss, of understanding.’ He becomes possessed of food, life, mind, understanding, and bliss who knows this. Verily, in as many things here on earth as do eat food does he eat food who knows this. Food does, indeed, prevent decay, Food is allaying, ’tis declared. Food is the life of animals, Is foremost, healing, ’tis declared.