Every thing you put in your mouth matters. A great rule of thumb to use when deciding if you should eat a certain food is, if you offered it to your great, great, great grandmother, what would she say about it? If she would happily accept your offering (knowing how it was grown and/or made) and gobble it up, then it is probably safe to eat. If, however, she would turn up her nose and look at it as if it were foreign garbage, then you should reconsider your choice.
Let your new pre-meal question be, "W.W.G.G.G.G.M.D? (What Would Great-Great-Great-Grandmother-Do?)