Body Composition, Changing Physiological Functions and Nutrient Requirements of the Elderly

Abstract

Age has an important impact on body composition. The decreases of lean body mass and total body water accompanied by an increase of body fat are the most relevant changes leading to a reduction of the basal metabolic rate. Due to this and the fact that elderly people are generally less physically active, energy needs are lower. However, the requirements for most micronutrients are not reduced. Indeed, impaired absorption of some vitamins and minerals like cobalamin and calcium can cause deficiencies. An adequate calcium supply is particularly important as with ongoing age, bone mass decreases as well, making elderly prone to osteoporosis. The reduced ability to synthesize vitamin D and the lower sunlight exposure of many elderly further aggravate this issue. There is evidence to consider the supply of some important dietary antioxidants as critical in some elderly, namely vitamin C and β-carotene as well as zinc. In light of age-related decreases in the activities of antioxidant enzymes, a sufficient supply of dietary antioxidants is important, especially as oxidative damage is thought to contribute to the deteriorating processes associated with aging and promote cardiovascular disease, cognitive disorders, cancer and diabetes mellitus that occur more frequently in older people. The first three are also associated with an insufficiency of folate, another critical nutrient in the elderly. Therefore, dietary guidelines should strive to optimize the immune function and reduce disease risk of the elderly.

Association between late-life body mass index and dementia

“…We also assumed that height was constant throughout the study period even though studies have shown that women and men lose 0.2 to 0.3 cm per year between the ages of 70 and 90 years 37 ; however, any error introduced would likely nondifferentially overestimate the rate of decline in BMI and not bias the findings. It is also possible that using BMI as our measure of weight may have underestimated adiposity in the elderly who generally have less lean body mass, 38 which would have attenuated our findings. Finally, we had insufficient power to detect a relationship between adiposity and VaD, but did find similar point estimates as dementia and AD.…”

l-Carnitine mediates protection against DNA damage in lymphocytes of aged rats

“…Nutrients with antioxidant properties play a vital role in fighting against free radicals and can modulate immune response (Elmadfa and Meyer 2008). The immunomodulatory effect of antioxidant compounds during aging has been well tabulated by De la Fuente (2002).…”

Food-derived peptidic antioxidants: A review of their production, assessment, and potential applications

“…However, the antioxidantprooxidant balance in human body can change with the progression of age and due to other factors such as environmental pollutants, fatigue, excessive caloric intake, and high fat diets. With advancing age, the plasma and cellular antioxidant potential as well as the absorption of nutrients, including antioxidants, gradually diminishes (Elmadfa & Meyer, 2008;Rizvi, Jha, & Maurya, 2006). Researches have in fact indicated an accumulation of protein carbonyls with the aging process in humans as a result of the action of free radicals on the proteins (Chakravarti & Chakravarti, 2007;Stadtman, 2006).…”