Keeping our brains healthy to reduce dementia risk

Research shows that our lifestyles can affect the health of our brains, and that making a few positive changes can help protect us as we get older. Dr Ivan Koychev is a clinician-scientist at Dementias Platform UK and a senior clinical researcher in Oxford University’s Department of Psychiatry.

Commenting in the Sunday Times this month – and as tens of thousands of people across the UK ‘Go Sober for October’ – dementia expert Professor John Gallacher (with whom I work closely) recommended a maximum alcohol intake of seven units per week to help reduce the risk of developing dementia.

As outlined by Professor Gallacher, Director of Dementias Platform UK (DPUK) and Professor of Cognitive Health at Oxford University, even low levels of alcohol consumption can cause harm to the brain. One recent study showed evidence that regularly drinking alcohol is linked to shrinkage of the hippocampus – an area of the brain affected by Alzheimer’s disease. There is no evidence that alcohol protects brain health.

Scientists like Professor Gallacher are working not only on potential new treatments for dementia, but also to encourage the adoption of ‘healthy brain lifestyles’ that could prevent it or delay its onset.

It is now well-recognised that the rate at which our brains age depends to a large extent on our lifestyles. In fact, it is thought that up to a third of all dementia cases are due to factors over which we have control.

The main examples are heart risk factors such as high blood pressure, diabetes, smoking and high blood lipids, but also importantly our activity levels. Time and time again as clinicians we see that the people who keep their brains healthy in older age are those who remain physically, mentally and socially active.

It may be tempting to think that it is dementia causing people to be less active in the first place, but experiments such as the FINGER study show that addressing heart and activity risk factors improves cognitive ability in people whose memories have already started to decline.

So as well as limiting alcohol consumption, what other lifestyle tweaks can reduce dementia risk?

Healthy heart

‘What’s good for the heart is generally good for the brain,’ said Professor Gallacher at a recent event celebrating five years of DPUK. Heart disease in midlife has been shown to contribute to poor brain health in later life. Evidence from the Cardiovascular Risk Factors, Aging and Dementia (CAIDE) study shows that high blood pressure, smoking, high cholesterol and diabetes significantly increase the risk of heart disease and strokes, which are linked to vascular dementia and Alzheimer’s disease. If you are affected by any of these conditions, your GP can help you make changes to your lifestyle or offer medication to improve your health.

Exercise

People who exercise regularly are more likely to keep their thinking and memory skills as they age. In general, exercise means aerobic activity that increases your heart rate and breathing – this might be brisk walking, cycling, swimming, or vigorous cleaning and gardening.

The findings of 15 studies show that exercise reduces the risk of poor brain health, although there is no evidence yet that it improves brain health. It is likely that exercise helps prevent dementia by reducing the risks from obesity, high blood pressure and heart disease, which are all in turn strongly linked to dementia.

The NHS has published some helpful national guidelines. Always consider your level of health when planning your exercise routine – ask your GP if you have any concerns.

Mental wellbeing

Mental wellbeing describes how you feel about and cope with day-to-day life. Studies show a link between dementia and anxiety and depression in midlife – however, what is not clear is the extent to which either depression is an early sign of dementia, or long-term depression causes changes in the brain that increase the risk of dementia. Nevertheless, anxiety and depression can have serious negative impacts on quality of life and impact one’s ability to address the other preventable risks for dementia.

Stress may also play a role in the development of dementia. It triggers the release of hormones such as cortisol that may directly affect the brain’s structure, and is associated with unhealthy behaviours like smoking and drinking that have in turn been linked with heightened risk of developing dementia.

Sleep is very important for mental wellbeing, as disrupted sleep and sleep deprivation are linked to poor memory and thinking skills. Research suggests that poor sleep might affect how efficient the brain is at clearing a protein that plays a significant role in Alzheimer’s disease.

There are many ways to boost your mental wellbeing. The NHS has published some actions people can take to reduce the likelihood of depression, anxiety and stress.

Cognitive wellbeing

Exercising your brain will help keep it young as it functions on a ‘use it or lose it’ basis. Reading, playing games and puzzles such as crosswords or Sudoku all make the brain work harder which can improve memory and thinking skills. This is particularly important in midlife, as those who regularly engage in intellectual, artistic and manual activities during that part of their life see less brain health decline as they age. However it is never too late to start.

Staying active socially

Staying active socially as you get older is crucial to maintaining brain health. Being social stimulates the brain, requiring it to process complex information so that we are able to adapt to other people’s behaviours and social situations.

There is growing evidence that loneliness may increase the risk of developing dementia. Social isolation increases the risk of high blood pressure, heart disease and low mood, all of which increase the risk of dementia.

Visit the Great Minds website for more information on how to keep a healthy brain, and to find out more about volunteering for dementia research.