Balancing protein intake, not cutting calories, may be key to long life

Getting the correct balance of proteins in our diet may be more important for healthy ageing than reducing calories, new research at UCL suggests. The new study may help explain why 'dietary restriction? (also known as calorie restriction) ' reducing food intake whilst maintaining sufficient quantities of vitamins, minerals and other nutrients ' appears to have health benefits. In many organisms, such as the fruit fly (drosophila), mice, rats and the Rhesus monkey, these benefits include living longer. Evidence suggests that dietary restriction can have health benefits for humans, too, though it is unclear whether it can increase longevity. Dietary restriction can have a potentially negative side effect, however: diminished fertility. For example, the female fruit fly reproduces less frequently on a low calorie diet and its litter size is reduced, though its reproductive span lasts longer. This is believed to be an evolutionary trait: in times of famine, essential nutrients are diverted away from reproduction and towards survival.