Yep.

A few times I've been ill and thought "Ah, it must have been..." and then realised that there was basically no time in which that could have taken effect - and re-eating that same meal had no effect.

I don't get ill often so it really sticks out in my mind and I try to find the cause and it's basically never attributable to food.

Part of that is because I cook everything "properly" (by which I mean, fuck your still-bloody steaks, if it hasn't changed colour all the way through it's going back on the heat) but also that I preserve my food well (freezing, refrigeration, keeping it sealed, etc.) and I avoid dodgy food (e.g. seafoods unless frozen and then well-cooked).

I have even once or twice taken to literally listing everything I'd eaten in the last few days, as far as memory will serve, and eliminating them as often I still have that food around... and I re-eat it and don't get a recurrence.

Sometimes it's nothing to do with your food, and sometimes people think it can't be anything to do with their food and it was from food from weeks ago.