This is pretty uncontroversial advice. In ecology, it's called being a "generalist". (And humans are generalists.) If you want to avoid all toxins ever, you'll

This is pretty uncontroversial advice. In ecology, it's called being a "generalist". (And humans are generalists.) If you want to avoid all toxins ever, you'll have to avoid... basically all food. Oxalic acid, cyanogenic glycosides, etc. are just freaking everywhere. Plants make defense compounds; we're able to handle small amounts of them.