Eating a little less might help you live longer. Like the Methuselah mice who enjoyed increased longevity after a reduced food intake, humans might also see more years by eating less dinner, according to new research.
The life-span of mice, rats, worms and other species have been extended in the laboratory by giving them a restricted diet that cuts the calories while still providing all the nutrients needed for a healthy life.
These calorie-restriction experiments have produced consistent results for years, but human volunteers have tended to be in short supply for obvious reasons.
You might live longer but would you really want those extra few years feeling hungry all the time?
Now researchers at the Pennington Biomedical Research Centre of Baton Rouge, Louisiana, believe they can show that caloric restriction can improve health in humans, at least in the short term.
They publish their findings in the open access journal PLoS (Public Library of Science) Medicine.
Rodent studies have shown that cutting food intake delays the onset of age-related diseases such as cancers, heart disease and stroke.
One theory of what produces these advantages relates to a reduction in "oxidative damage". The breakdown of the food we eat causes the production of free radicals. These damaging chemicals are produced in cellular structures called mitochondria.
Free radicals damage DNA and hasten age-related illnesses, so reducing them should be a good thing. The research group, led by Dr Anthony Civitarese, showed that humans who ate less had more efficient mitochondria that produced fewer free radicals, causing less DNA damage.
The researchers enrolled 36 healthy overweight but non- obese young people into the study.
These were divided into three groups, one which ate a full normal diet, another which had calorie intake reduced by 25 per cent and a third group which had calories reduced by 12.5 per cent and whose exercise increased to burn up another 12.5 per cent of their calories.
After what must have seemed a long six months for some, the researchers said the dieters and the diet/exercise group both showed improved mitochondrial performance. Those who ate a normal diet showed no change.
The researchers also showed that a particular gene that becomes more active in calorie- restricted yeast, worms and flies helping them to live longer, also becomes more active in humans.
"The results suggest that even short-term caloric restriction can produce beneficial physiological changes leading to improved health," the researchers concluded.
"Whether caloric restriction and the associated health benefits can be sustained over longer term remains to be established in humans."