The UK is experiencing an ageing population but this is not matched by a similar increase in healthy life expectancy. Some of the major biological life changes associated with ageing result from the accumulation of lifelong molecular damage to cells, but many health problems are attributable to lifestyle and environmental factors. Diet is one factor believed to play a key role in the prevention and treatment of chronic diseases associated with ageing. Diets that are high in total fat, saturated fat and salt, and low in fibre, fruits and vegetables, are central to the development of CVD, type 2 diabetes and cognitive decline among elderly people. In contrast, under nutrition is also a major problem in this age group, with many elderly people having low intakes of essential vitamins and minerals. Good nutrition is essential for healthy ageing and a multi-disciplinary, life-course, approach to ageing is vital in minimising its implications for quality of life and public health.