Other than fruit (a seed dispersal mechanism), most “food” doesn’t actually want to be eaten.
A good way to protect yourself from being eaten is to become poisonous.
We’ve evolved ways to become immune to some of those poisons, or more recently, we’ve bred plants to be less poisonous.
Is this about spicy food?
Probably onions, chocolate, and grapes.
Alcohol, mangoes, kiwi, actually a lot of fruits have compounds in their skins which you’d call poisonous. Some nuts, definitely peppers, a lot of seasonings, coffee and tea, hell even some meats we eat aren’t really “safe,” and let’s not forget that milk isn’t “supposed” to be consumed much past early childhood.
Could be about anything fermented.
Idk, my dog eats a lot of shit that would kill me. Including literal shit.