There are however highly processed 'foods' such as HFCS which have no food value and which are arguably poisonous.
There is also modern wheat. For all of its benefits as a crop it is no longer the 'staff of life' - modern dwarf-wheat processed into white flour is responsible for chronic digestive and inflammatory illnesses.
I believe that grains cause the scaring of the arteries that result in cholesterol buildup and subsequent heart disease. I have cut grains out of my diet. No Grains. No Sugar. No processed foods. Eat only foods that come without a list of ingredients.
And when I say no, I really mean except on rare occasion. I truly enjoy a fine chocolate and an occasional piece of bread. But I dropped 45 lbs and 4 inches of belly fat with my diet.