Nutrition advice is confusing. Scientists have difficulty deriving clear guidelines because a study of an individual nutrient fails to produce an understanding of what happens to it when mixed with other nutrients in the body.

The picture becomes more clouded because industry groups constantly press their message to both government agencies and consumers about the benefits of eating particular food products.

The simplest message may be the best: do not overeat, exercise more, consume mostly fruits, vegetables and whole grains, and avoid junk foods.
—The Editors