A Biological Perspective of Ageing

Geriatric medicine is necessary because of the biological changes that take place in our bodies with time. Ageing is not programmed into us. Rather, our bodies do not need to be maintained optimally after reproduction. Biological ageing progresses differently in different cells and tissues and organisms. There is no one 'theory of ageing' that accounts for all the features of biological ageing. However, there are different perspectives at different levels of biological organization. These include free radical, mitochondrial, and gene expression perspectives (subcellular level), cell senescence and stem cell perspectives (cellular level) and neuroendocrine and immune perspectives (systemic level). Although biological ageing results in increased vulnerability to disease, it is different from the diseases of old age. There is experimental evidence that even in mammals morbidity can be decreased and longevity increased at a fundamental biological level. However, at the present time we provide care mostly at the level of the diseases of ageing.