Low calorie diets may slow the process of ageing by affecting the behaviour of hundreds of genes, say researchers.
They found calorie-reduced diets stop the normal rise and fall in activity levels of close to 900 different genes linked to ageing and memory formation in the brain.
An experimental study suggests for the first time that food restriction – particularly carbohydrates – may work by manipulating the function of a much larger group of genes than previously suspected.
Low carb, calorie-reduced diets affect 900 different genes linked to ageing and memory formation in the brain
Dietary restriction has been known for decades to extend life in a range of animals, but it has proved difficult to achieve in practice and the mechanisms involved have eluded scientists.
Dr Stephen Ginsberg, a neuroscientist at New York University’s Langone Medical Centre who led the study, said: ‘Our study shows how calorie restriction practically arrests gene expression levels involved in the ageing phenotype – how some genes determine the behaviour of mice, people, and other mammals as they get old.’
However, he warned it does not mean calorie restriction is the ‘fountain of youth,’ although it will ‘add evidence for the role of diet in delaying the effects of ageing and age-related disease.’
Dr Ginsberg said the benefits of such diets have been touted to include reduced risk of human heart disease, high blood pressure and stroke, but the widespread genetic impact on the memory and learning regions of ageing brains has not before been shown.
He said previous studies have only assessed the dietary impact on one or two genes at a time, but his analysis encompassed more than 10,000 genes.
Dr Ginsberg, an associate professor at NYU Langone said the research ‘widens the door to further study into calorie restriction and anti-ageing genetics.’
For the study, female mice, which like people are more prone to dementia than males, were fed food pellets that had 30 per cent fewer calories than those fed to other mice.
Tissue analyses of the hippocampal region, an area of the brain affected earliest in Alzheimer’s disease, were performed on mice in middle and late adulthood to assess any difference in gene expression over time.
Diets such as these have been linked with a delayed onset of ageing and diseases such as heart disease, high blood pressure
The findings were presented today at the Society for Neuroscience’s annual meeting in Washington DC.
Dr Eric Karran, Director of Research at Alzheimer’s Research UK, said: ‘This study suggests that a calorie-restricted diet could influence a large group of genes in the female mouse brain which are associated with ageing, but it’s not clear whether these changes would translate into benefits for learning and memory in these mice.
‘Interventional studies would be needed in people to determine what impact calorie restriction might have on long-term health and age-related memory impairment.
‘As we know, many people would find it challenging to sustain such a calorie-restricted diet, even if it was shown to be beneficial to brain health.
‘It’s important to maintain a balanced and healthy diet, particularly into older age, and if people are considering making large changes to their diet they should consult their doctor.
‘Current evidence suggests that the best way to maintain a healthy brain into older age is to not smoke, keep a healthy weight, eat a balanced diet, drink only in moderation and keep high blood pressure and cholesterol in check.’