Three hours would be fine. In a pinch I'll eat stuff that's been there overnight. I don't do it unless I have to, and to be honest, I have no problem going 10 hours+ without food, but sometimes you're in the middle of nowhere in masai warrior territory and all there is was last night's kill....it's all about perspective. If you give your body a fighting chance through a nutritionally excellent diet, then you can fudge it here or there. Sticking to unprocessed foods is a huge step forward. Till that's mostly sorted I wouldn't stress too much about foods that are less than 24 hours from cooking.
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