Improved diet in middle age may extend life

Eating less in middle age could extend longevity, a study of mice suggests.

The research suggests a low-calorie diet can slow the heart's ageing process and extend its working life.

Scientists from the University of Wisconsin-Madison found middle-aged mice on calorie-restricted diets had stronger hearts in old age.

Numerous studies on animals have shown nutritious diets low in calories can result in significant health benefits, slow ageing and extend longevity. In some cases, the life-spans of animals in experiments have been increased by as much as a third. Even when calorie intake was not restricted until middle age, the life-span of mice increased by 20 per cent.

The Madison scientists examined the genetic changes associated with the ageing process of the heart.

The results, in the Proceedings of the National Academy of Sciences, suggest calorific restriction inhibited the genes involved in cell death and which inflame heart cells, leading to heart failure.

Professor Tomas Prolla, who led the study, said: "The most surprising thing to me is that calorific restriction, even when started in middle age, has a very strong effect on changes that occur with ageing."

Professor Tom Kirkwood, of the Institute for Ageing and Health at Newcastle University, said it was important to understand how older hearts become more vulnerable to failure. "This research helps us in our quest to get at how the heart ages. It confirms that an extreme, low-calorie diet delays the appearance of age-related changes in the hearts of these animals."