Bhagwad Gita
Chapter 6, Verse 16
नात्यश्नतस्तु योगोऽस्ति न चैकान्तमनश्नतः।
न चातिस्वप्नशीलस्य जाग्रतो नैव चार्जुन।।6.16।।
There is no possibility of one's becoming a yogi, O Arjuna, if one eats too much, or eats too little, sleeps too much or does not sleep enough.