Food : what the heck should I eat?

Even the most health conscious among us have a hard time figuring out what to eat in order to lose weight, stay fit, and improve our health. And who can blame us? When it comes to diet, there's so much changing and conflicting information flying around that it's impossible to know where to look for sound advice. Dr. Mark Hyman takes a close look at every food group and explains which foods nurture our health and which pose a threat. From grains t...