Nutritional requirements of the elderly

Abstract

Nutritional issues should be addressed not only for the 1990s but also for the 21st century. A remarkable demographic change which has occurred over this century will accelerate into the next. In America now, as in many European countries, those over the age of 65 are about 1 in 9 of the population. Early next century they will be 1 in 5, a number which has already been achieved in Japan. It is generally agreed that this change in one century, from 1 in 25 of the population over age 65 in 1900 to 1 in 5 early in the 21st century, represents perhaps one of the most remarkable demographic changes that have been experienced in modern history and presents an enormous health challenge. Many of the conditions that afflict the elderly have been discussed in this meeting. Almost any kind of physiological function, whether it be renal concentrating function, pulmonary function, cardiac output or glucose tolerance, has been shown in cross-sectional studies to decline over the age span. Thus one clear goal of medical science should be to prevent, to the extent possible, those diseases and/or functional declines which contribute to debility and dependence in the elderly. Thus, nutritionists are therefore reflecting on the ageing process itself and the question of how many of these declining functions are, in fact, inevitable. The biological lifespan is probably fairly well defined by species and genetic heritage. Nutritionists ought therefore to be considering whether we can achieve a lifestyle of habit and diet so that physiological functions are retained through the span of age. The primary aim should therefore be to strive for an elderly population that is more vigorous, more active and more independent.