Spread carnage and corruption!
Henzell says...
  1. Prior to the removal of food in 0.26, casting a spell lowered your nutrition by an amount varying with the spell's level: (1) 50, (2) 100, (3) 150, (4) 250, (5) 400, (6) 550, (7) 700, (8) 850, (9) 1000. This amount was lowered by the product of your Intelligence and Spellcasting.
  2. N hashes means that a spell costs more than 10*N*(N-1) nutrition to cast.

Information based on master branch and the great LearnDB.
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