Ever since sailors noticed that scurvy could be prevented with citrus fruits, it has been clear that illness could be caused by a lack of certain nutrients. While nutrient-enriched products have reduced diseases caused by vitamin deficiency in the developed countries, the problem continues to plague the developing world. And many in poorer countries suffer from the twin problems of poor nutrition and unsafe water, which create a disease burden that is almost unbearable. Back to the Basics explores the connection between health and the essential requirements that so many people take for granted. It also examines how an overabundance of nutrition — in the form of over-consumption — is causing an epidemic of obesity that is spreading across the globe.