Grain processing and nutrition

Whole grains provide a wide range of nutrients and phytochemicals that opti mize health. Epidemiologic studies support the protectiveness of whole grai n consumption for cardiovascular disease and cancer. Dietary guidance endor ses increased whole grains in our diet. A crucial question remaining is the effect of processing of whole grains on their content of nutrients and phy tochemicals. Although processing is often considered to be a negative attri bute in nutrition, and some forms of processing reduce nutritional value, m any factors support the importance of processing of grains to enhance grain consumption. First, whole grains as harvested are generally not consumed d irectly by humans but require some processing prior to consumption. While r efining, that is, removal of the bran and the germ, reduces the nutrient co ntent of grain, milling of grains otherwise concentrates desirable grain co mponents and removes poorly digested compounds and contaminants. Cooking of grains generally increases digestibility of nutrients and phytochemicals. Studies in both animal models and humans support the notion that processed grains are often nutritionally superior to unprocessed grains, probably bec ause of enhanced nutrient bioavailability in processed grains. Processing o f grains also provides shelf-stable products that are convenient and good t asting for consumers.