A DAILY dose of cocoa could be the secret to halting Alzheimer’s disease, researchers claim.
Scientists have found that the potent ingredient in chocolate can dramatically improve cognitive impairment.
Experts say pensioners should have some cocoa every day in a bid to keep dementia and Alzheimer’s at bay.
The key lies in health-boosting flavanols which are abundant in the sweet treat.
Flavanols are an antioxidant also found naturally in fruit and vegetables such as grapes, berries and apples, drinks including tea and red wine, and other plant-based foods.
Dr Giovambattista Desideri, who headed the research team, said: “This study provides encouraging evidence that consuming cocoa flavanols as part of a calorie-controlled and nutritionally balanced diet could improve cognitive function.
“Given the global rise in cognitive disorders, which have a true impact on an individual’s quality of life, the role of cocoa flavanols in preventing or slowing the progression of mild cognitive impairment to dementia warrants further research.”
Flavanols belong to a group of compounds called flavonoids which have been shown to help beat cancer, heart disease and the ageing process by protecting cells. They also mop up potentially harmful oxygen molecules in the body.
Researchers from the University of L’Aquila in Italy found that eating cocoa flavanols daily could improve mild cognitive impairment (MCI), the precursor to the brain condition.
MCI is characterised by the memory loss that comes with ageing, which precedes full dementia. About 60 per cent of those with this impairment go on to develop Alzheimer’s.
In the new study, published in the journal Hypertension, 90 elderly people with MCI had 990mg (high), 520mg (intermediate) or 45mg (low) of a cocoa flavanol drink daily for eight weeks. Their diet was restricted to eliminate other sources of flavanols.
Tests for cognitive function included short-term memory, long-term episodic memory and processing speed.
Researchers found scores significantly improved in the ability to relate visual stimuli to motor responses, working memory, task-switching and verbal memory for those on the high and intermediate flavanol drinks.
Those who drank higher levels had significantly improved overall cognitive scores than those on lower levels.
Blood pressure and insulin resistance, where the hormone is less effective at lowering blood sugars, also decreased in those taking high and intermediate flavanol levels. Changes in insulin resistance explained about 40 per cent of the scores for improvements in cognitive function.
Dr Desideri said: “The positive effect on cognitive function may be mainly mediated by an improvement in insulin sensitivity.
“It is yet unclear whether these benefits in cognition are a direct consequence of cocoa flavanols or a secondary effect of general improvements in cardiovascular function.
“Larger studies are needed to validate the findings, figure out how long the positive effects will last and determine the levels of cocoa flavanols required for benefit.” Previous research has shown that chocolate and cocoa products can decrease the risk of dementia.
They may protect neurons from injury, improve metabolism and interact with the molecular structure responsible for memory, researchers said. Indirectly, flavanols improve brain blood flow.
Alzheimer’s occurs with a build-up of amyloid plaques, proteins that group together causing blockages and reducing normal brain functioning.
Dr Laura Phipps, of Alzheimer’s Research UK, said: “It would be useful to see more long-term studies to investigate the lasting effects. Ultimately we would need to see the results of large-scale trials to know whether cocoa flavanols could help prevent or delay dementia.”