Research suggests that the Western diet is a contributory factor in the low micronutrient intakes of many living in developed nations. Growing evidence suggests that those individuals with the lowest intakes of certain micronutrients may be at increased risk of disease. Further, within the developed nations, particular sub-groups may have especially low intakes of micronutrients due to particular lifestyle habits and food choices. For example, the institutionalised elderly have consistently been shown to have poor micronutrient status, which may increase significantly their risk of developing certain diseases including mental deterioration and dementia. The reason for their poor micronutrient status has been speculated to be due to a combination of low quality diets and an age related decreases in nutrient absorption. However, that elderly populations eating high quality diets do not show age related signs of disease (here) suggests that nutrient absorption is not as large a factor in this process as has been suggested.
The use of supplements has been shown to improve the micronutrient status of the elder. This provides further evidence that while absorption may play a role in the diminishing nutrient status of the elderly, it is not the defining parameter. Studies have shown that supplementation of the elderly with micronutrients can rapidly reverse deficiencies and correct plasma levels to those of younger more healthy individuals. For example, in one study published in the American Journal of Clinical Nutrition1, researchers investigated the effects of vitamin C supplements on chronically sick and elderly patients (average age 73 years) in comparison to a control group of young women (average age 36 years). Supplementation of the elderly subjects with 30 mg of vitamin C per day (a small dose, half the recommended level) caused a rapid increase in plasma levels of vitamin C. When the dose was increased to 50 mg per day, the plasma level rose further, finishing five-fold higher than initial values. Those receiving no vitamin C showed no change in plasma levels.
Supplementation of the elderly subjects with 100 mg per day caused the plasma levels of vitamin C to rise above those of the younger women. Therefore supplementation with even a modest dose of just under two times the recommended intake causes a reversal of chronic deficiency. The authors pointed out that some of the hospitalised elderly patients in this study had vitamin C plasma levels in the scurvy range (less than 0.1 mg per 100 mL plasma). The efficacy of supplements at reversing this deficiency state suggests that absorption is not a barrier to maintaining adequate plasma levels of vitamin C. Instead, poor diet with low concentrations of vitamin C is the likely cause of the poor vitamin status of the elderly. While supplements were used in this study, it is interesting to speculate what may have happened if fruit rich in vitamin C had been used instead. In this respect, there is no reason to believe that the vitamin C from whole foods would not have also caused a significant improvement in the vitamin C status of the subjects.
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