What Is Ojas and Why Does Sleep Either Build or Deplete It? Ojas is the refined vital essence produced when strong agni transforms food through all seven tissue layers -- the Ayurvedic substrate of immunity, resilience, and the capacity for genuine happiness. Sleep either builds or depletes Ojas depending entirely on its quality and timing, not its duration. Sleep during the Pitta recovery window (10pm-2am) that is deep and uninterrupted builds Ojas. Sleep that is late, fragmented, preceded by alcohol or heavy food, or disrupted by screens and stress depletes Ojas even when the total hours are adequate. This is why you can sleep eight hours and still wake depleted. The question I get most often is some version of: I am sleeping enough but I am still exhausted. I feel like I should be recov