Scientists have found that cutting calorific intake can help rodents to live longer and said they hope to develop drugs that mimic the process in humans.
New research from the University of Florida shows that dietary restriction increases cells' ability to produce energy efficiently.
Dr Christiaan Leeuwenburgh, from the University's Institute on Ageing, said: "Caloric restriction is a way to extend life in animals. If you give them less food, the stress of this healthy habit actually makes them live longer."
During the ageing process, free radicals damage mitochondria, the tiny power houses of the cell. This results in cell death, unless the damaged mitochondria are recycled, as is common in younger cells. The recycling mechanism is called autophagy.
A low-calorie diet was enough to boost cellular cleaning in the hearts of older rats by 120 percent above levels seen in rats that were allowed to eat what they wanted.
Senior author Dr William Dunn said research in the area should now look to bypassing calorific restriction and find another means of increasing autophagy.
"That is, instead of starving yourself you can find another way of enhancing autophagy that will allow the enhanced removal of various damaged organelles that accumulate in aged cells."