The most feasible way to introduce iodine in the ration will be in the form of iodized salt. It is recommended that iodized salt contains 20-40 mg of iodine per kg of salt IOM, 2002b. Since iron deficiency is rare in men, if there are palatability or stability problems, the level could be ny to the 8 mg level, the RDA for men. Iron functions in oxygen transport and energy utilization as a cofactor for a number of enzymes involved in energy metabolism. Basal losses include fecal losses, urinary losses, and losses due to normal skin and miscellaneous losses.
The median dietary intake is 17. Clinical effects of deficiency include impaired physical and cognitive performance. The estimate of bioavailability 18 percent is based on an assumption that 10 percent of the iron in the daily diet will come from heme iron, 25 percent of which fres absorbed Hallberg and Rossander-Hulten, 1991and 90 percent will come from non-heme iron sources, of which approximately 17 percent is absorbed Cook et al. In the absence of heme iron, estimates of bioavailability drop to 10 percent IOM, 2001b.
As iron stores rise, there is a decrease in the percent of dietary iron that is absorbed, thus decreasing the availability of dietary iron. Iron Status and Physical Performance. The impact of adequate iron and iron supplements on maintenance and possibly enhancement of physical performance was evaluated during write my paper me free training and in endurance athletes Newhouse and Clement, 1988. Write my paper me free studies of iron were with female athletes, many of whom had evidence of iron depletion or anemia or both see Lukaski and Penland, 2004 in Appendix Hematological write my paper me free such as hematocrit, hemoglobin, and serum iron were decreased in response to intense exercise maintained over time.
Laper on review of over 20 years of research on iron and athletic performance and health, Beard and Tobin 2000 concluded that reductions in hemoglobin concentration and tissue iron content can be detrimental to exercise performance, and that iron status is negatively altered in many populations writs chronically exercising individuals. Decreased hematocrit and hemoglobin impair the delivery of oxygen to the tissues and lead to a reduced VO2max.
Supplementation of individuals with iron to a normal hematocrit improves VO2max Beard and Tobin, 2000 and, hence, exercise capacity and performance Woodson, 1984. Deficits of the nonheme iron that is associated with enzyme systems e. Iron-depleted, nonanemic women engaged in aerobic training were studied for six weeks with or without iron supplementation Brownlie et al. Improvements in measures of endurance capacity with training were lower in those with tissue iron deficiency and provision of supplementary iron reversed this decrease.
A subsequent placebo-controlled study from the same laboratory in similar iron-depleted, nonanemic women found that iron supplementation improved indices of progressive muscle fatigue resistance Brutsaert et al. Note that these were untrained women, which may not be analogous to what might be expected among men in assault operations. A study of Australian soldiers consuming combat rations during operations in Australia Booth et al. Ferritin levels in those soldiers receiving only one-half the combat ration pack estimated to consume about 1,600 kcal dropped by 17 percent over the 12-day operation.
However, in this paper, no conclusion was made about the consequences of the alteration in ferritin status on health or performance. Iron Status and Mental Performance. The association of iron deficiency anemia with impaired mental performance has been noted for many years, particularly in infants and young children IOM, 2001b. Of interest to developing the assault ration are data on the use of iron supplementation to improve attention and short-term memory in adolescent girls who were iron write my paper me free but not anemic Bruner et al.
Accuracy and attention- memory- and learning-reaction times were directly related to higher ferritin and transferrin saturation in young women while, in other studies, markers of cortical activation were directly related to serum iron and ferritin levels see Lukaski and Penland, 2004 rfee Appendix Given the reported increased feelings of fatigue, loss of vigor, and confusion as well as decreased serum ferritin levels mj dehydration when consuming restricted rations Booth et al. Iron Status and Immune Function. Exercise affects iron requirements and metabolism Gleeson et al. Reallocation of mw circulating and body iron stores occurs due to significant physical activity and resulting high energy expenditure and iron sweat losses may result in impaired immune function.
Maintaining optimal resistance to infection is a complex process that involves many nutrients, including iron. Some ffree have shown that infection by specific pathogenic organisms e. In addition, other studies suggest that continued use of oral or parenteral iron or the presence of excessstored iron as a result of hemochromatosis may be associated with enhanced susceptibility to infections Gleeson et al.college essay proofreading services what are the best essay writing services i need help writing an essay i need help with my high school essay write my scholarly paper