There is no proven way to significantly lower your risk of dementia, researchers warn in the biggest investigation ever done on the disease.
In the age of supplements, it may seem like there is a pill or wellness regime to fix everything.
But experts insist there is no ‘magic bullet’, and anything which pits itself as such is duping the consumer.
They concede that exercise and a good diet may be somewhat effective, since they decrease inflammation in the body and dementia is linked to inflammation in the brain.
However, people who exercise five times a week are not immune to Alzheimer’s, and we are still far off discovering the ‘key’ to preventing the disease.
It may seem like there is a pill to fix everything. But a University of Minnesota study warns there is no ‘magic bullet’ for dementia, and anything pitting itself as such is duping you
The researchers at the University of Minnesota reviewed 116 previous trials looking into the effect of exercise, vitamin supplements, cognitive training and exercise and were ‘disheartened’ by the findings.
Professor Howard Fink, an internist, said: ‘One of several of the studies that looked at the effect of combining specific interventions – cognitive training, exercise and diet – showed some improvement in cognitive outcomes.’
He said beginning these as early as possible could have some protective effect – but the vast majority of research showed none of the methods worked.
‘We looked at drugs, over-the-counter vitamin supplements, exercise, cognitive training and overall the results didn’t show much benefit,’ he added.
His team reviewed published research on whether physical activity, prescription medications, over-the-counter vitamins and supplements or cognitive training could help prevent dementia.
Study co-author Dr Mary Butler said: ‘There is no magic bullet. But those areas we did find potentially positive findings are very consisent with public health types of messages we hear all the time.
‘Live a healthy life, eat a good diet, stay cognitively active and engage socially.’
The study, published in the journal Annals of Internal Medicine, said the prevalence of dementia is expected to increase dramatically as the population ages.
More than 5.5 million Americans suffer from Alzheimer’s, and those numbers are only expected to climb as the population ages. In the UK alone there are 850,000 sufferers – a number that will soar to million by 2050. There is no cure.
As far as physical activity goes the researchers analysed data from 16 trials and found insufficient evidence to draw conclusions about the effectiveness of aerobic training, resistance training or the gentle martial art tai chi for improving brain power.
But there was ‘low-strength evidence’ combining different types of interventions at the same time – such as physical activity, diet and cognitive training – boosted mental performance.
A review of data from 51 trials of aspirin and other prescription pills did not support use of any for cognitive protection.
Likewise 11 trials of adults with either normal cognition or mild cognitive impairment – memory loss that can lead to dementia – failed to show brain training exercises were effective.
Group cognitive training was found to improve performance only in the cognitive domain trained. For example, memory training improved memory, but did not improve any other aspects of cognition.
Dr Butler said: ‘When we looked at the evidence for group cognitive training what we found was people improved in areas they trained in but that training did not extend to other areas.
‘If you train in processing speed there wasn’t improvement in memory.’
The team also reviewed 38 trials comparing over-the-counter supplements including omega-3 fatty acids, soy, ginkgo biloba, B vitamins, vitamin D plus calcium, vitamin C or beta carotene and multi-vitamin pills.
They found insufficient evidence to suggest that any of the supplements worked to reduce the risk for cognitive decline.
But the researchers said the reasons these interventions fail is not entirely clear.
It’s possible they simply do not work to improve cognition – or it could also be the studies started the interventions too late in life, didn’t use them long enough or because of other shortcomings.
Professor Fink said: ‘Leading a healthy lifestyle early in life could be the best defense against cognitive decline later – but definitive evidence is lacking.’
He said while there was no evidence it protects against cognitive decline or dementia it’s unlikely to worsen cognition – and may have other, non-cognitive benefits.