[below is an excerpt from Michael Pollan's book The Omnivore's Dilemma]
"The ingredients listed in the flyer ["A Full Serving of Nutrition Facts", given out by McDonalds] suggest a lot of thought goes into a nugget, that and a lot of corn. Of the thirty-eight ingredients it takes to make a McNugget, I counted thirteen that can be derived from corn: the corn-fed chicken itself; modified cornstarch (to bind the pulverized chicken meat); mono-, tri-, and diglycerides (emulsifiers, which keep the fats and water from separating); dextrose; lecithin (another emulsifier); chicken broth (to restore some of the flavor that processing leaches out); yellow corn flour and more modified cornstarch (for the batter); cornstarch (a filler); vegetable shortening; partially hydrogenated corn oil; and citric acid as preservative. A couple of other plants take part in the nugget: There's some wheat in the batter, and on any given day the hydrogenated oil could come from soybeans, canola, or cotton rather than corn, depending on market price and availability.
According to the handout, McNuggets also contain several completely synthetic ingredients, quasiedible substances that ultimately come not from a corn or soybean field but from a petroleum refinery or chemical plant. These chemicals are what make modern processed foods possible, by keeping the organic mterials in them from going bad or looking strange after months in the freezer or on the road. Listed first are the "leavening agents": sodium aluminium phosphate, (etc...) . These are antioxidants added to keep the various animal and vegetable fats involved in a nugget from turning rancid. Then there are "anti-foaming agents" like dimethylpolysiloxene, added to the cooking oil to keep the starches from binding to air molecules, so as to produce foam during the fry. The problem is evidently grave enough to warrant adding a toxic chemical to the food: According to the Handbook of Food Additives, dimethylpolysiloxene is a suspected carcinogen and an established mutagen, tumorigen, and reproductive effector; it's also flammable.
But perhaps the most alarming ingredient in a Chicken McNugget is tertiary butylhydroquinone, or TBHQ, an antioxidant derived from petroleum that is either sprayed directly on the nugget or the inside of the box it comes in to "help preserve freshness." According to A Consumer's Dictionary of Food Additives, TBHQ is a form of butane (i.e., lighter fluid) the FDA allows processors to use sparingly in our food: It can comprise no more than 0.02 percent of the oil in a nugget. Which is probably just as well, considering that ingesting a single gram of TBHQ can cause "nausea, vomiting, ringing in the ears, delirium, a sense of suffocation, and collapse." Ingesting five grams of TBHQ can kill."
One in three kids eats fast food every day. Let me suggest this - BUY THIS BOOK and read it cover to cover, and take notes all the while. I am only ~40% through it and I'll already name it among the best books I've read.