Crossword clue: of or performance to diet, or to the rules for regulating the kind and quantity of food to be eaten.

The most common answer is dietetic (8 letters).

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

Possible answers

dietetic 8 letters web-def

of or relating to the diet

dietetical 10 letters web-def

Of or performance to diet, or to the rules for regulating the kind and quantity of food to be eaten.