I'm reading a great book right now that I just had to tell you about! It's called Salt Sugar Fat, by Michael Moss, and it's about the history of processed foods. I'm only partially through the first section, which is about sugar, and I've already learned so much!
This book just reinforces my belief that we need to be eating whole, real foods, not things that come packaged full of chemicals and additives. It's scary how little the companies who manufacture processed food think of the health of the people actually eating it.
I definitely think you should read this book, but if you just want the main point, here it is: eat real food! Don't trust companies that are out to make a profit with your health.