Nutrition during the lifecycle: nutritional needs of older adults
The nutritional status of an older person is a major determinant of both physical and cognitive functioning, as well as overall independence and quality of life. Moreover, nutrition is closely involved in the aetiology and management of various chronic diseases, such as cardiovascular disease and certain cancers (discussed in Chapter 7). The eminent gerontologist Prof. John Rowe [1) proposed the term 'successful ageing' to characterise the process of growing older while retaining satisfactory health, function and independence (Figure 8.1). This is contrasted to two other conditions: normative ageing and frailty. Normative ageing is the experience that covers many of the advanced years of most older persons in which multiple chronic diseases appear, and function is compromised to some degree. Frailty is at the other end of the spectrum: frail older persons have severe decline in cognitive and physical function, losing independence in activities of daily living, often becoming wheelchair-bound or bedridden, and requiring assistance and care. Older individuals of a similar age may be at any stage in this continuum of dependency, and thus have markedly different risk factors and requirements leading to heterogeneity in this age group.