Nearly half of Americans take at least one prescription medicine, with almost a quarter taking three or more, as diseases such as diabetes, obesity, and dementia grow more prevalent than ever. The problem with medicating common ailments, such as high blood pressure or elevated cholesterol, is that drugs treat symptoms--and may even improve test results--without addressing the cause: diet.

Overmedicated, overfed, and malnourished, most Americans fail to realize the answer to lower disease rates doesn't lie in more pills but in the foods we eat.

With so much misleading nutritional...