Many reports in the scientific literature are causing nutritional scientists to question the traditional assessments of nutritional adequacy. The current U.S. Recommended Dietary Allowances are in the process of being revised and updated; the Dietary Reference Intakes, as they will be known, will present recommended adequate levels of the nutrients for selected populations. The publicity concerning the recent research on the effect of perinatal folic acid supplementation on the incidence of congenital neural tube defects is a good example of a research finding that challenges the traditional view of nutrient adequacy.
One area of active research of particular concern to this readership involves assessment of nutritional adequacy based on immune responses. This is of particular importance to military operations during periods of extreme physical and psychological stress. Considerable interest in the exercise physiology and nutrition literature during the past 5 years focuses on the interaction of nutrition and susceptibility to infection in athletes training for competition. Although close analogies can be drawn between training for an athletic event and military combat training, some important differences need to be addressed. While an athlete is usually well rested and fed a diet specific to his or her sport and nutritional needs, individuals involved in combat training are often sleep deprived and fed ''one-size-fits-all'' military operational rations. Another important difference is that soldiers often suffer abrasions and cuts, which increases the chance for opportunistic infection.
Special Operations training offers the unique opportunity to determine the extent of immunological perturbations during military training. Furthermore, the structured nature of the training schools provides the opportunity to conduct controlled research studies designed to screen nutritional strategies that may be effective in sustaining immune responses during the stress of combat training. During the past 4 years, a number of field studies related to this issue have been conducted in collaboration with the Ranger Training Brigade (RTB), Fort Benning, Georgia, and the Special Warfare Training Center, Fort Bragg, North Carolina.
The research conducted in these locations has been guided by two primary research objectives: