Eating more berries, tea, red wine and dark chocolate could lower your risk of dementia, a new study from Queen’s University Belfast has found.

Berries and wine are rich in flavonoids, compounds found in many plants that appear to be beneficial to heart health and blood pressure.

Lowering blood pressure is associated with significant lowered risk of dementia.

Flavonoids are also said to have powerful antioxidant and anti-inflammatory properties. These could mitigate the effects of stress and inflammation that contribute to cognitive impairment.

By adding six servings of these foods a day, the researchers say, the risk of developing dementia could be cut by 28 per cent.

You need to keep in mind that the 28 per cent lowered risk is what you gain when compared to people who don’t boost their diet with flavonoids.

It doesn’t mean that your overall risk of dementia is cut by more than a quarter. There are simply too many other factors at play.

It simply means, that in your arsenal of weapons against developing dementia, flavonoids are one more helpful thing.

On their own, they’re probably not going to get you off the dementia hook.

This was a population-based cohort study, which analysed dietary data from more than 120,000 adults aged between 40 and 70 years from the UK Biobank.

Interestingly, the benefit was “most noticeable in individuals with a high genetic risk” and those with symptoms of depression.

Flavonoids, blood pressure

The study was led by Professor Aedín Cassidy, from Queen’s Institute for Global Food Security.

Cassidy has worked in dietary polyphenol research since 1988 and her research focuses on understanding the impact of a range of plant bioactives, including flavonoids, on cardiometabolic health.

In a fascinating 2021 study, Cassidy found that a higher intake of flavonoid-rich foods was associated with a clinically relevant reduction in blood pressure levels – which wasn’t news.

The interesting thing was the association, between flavonoids and lowered blood pressure, was “partially explained by characteristics of the gut microbiome”.

Namely, up to 15 per cent of the observed association was explained by the gut microbiome. This suggests these microbes play a key role in metabolising flavonoids “to enhance their cardioprotective effects”.

Presumably, the healthier your gut microbiome, the more effective the flavonoids are in lowering hypertension.

A 2012 study found that flavonoid-rich blueberries and strawberries appear to reduce cognitive decline in older adults.

The study found that cognitive ageing could be delayed by up to 2.5 years in elderly berry eaters.

Dr Tian-Shin Yeh is a researcher in the area of diet and cognitive function with Harvard’s TH Chan School of Public Health. She wasn’t involved in these studies.

In an article from Harvard Medical School, she said: “The more we learn about flavonoids’ role in health, the more we find that they may have far-reaching potential in helping to protect an ageing brain.”

But not the whole story

About two weeks ago, The Lancet published a stunning report that found nearly half of all dementia cases could be delayed or prevented altogether.

This could be done by addressing 14 possible risk factors, including vision loss and high cholesterol.

Two of the authors, in a Conversation article, laid out a dementia-protection plan over a person’s lifetime.

The key points included:

• In early life, improving general education
• In midlife, addressing hearing loss, high LDL cholesterol, depression, traumatic brain injury, physical inactivity, diabetes, smoking, hypertension, obesity and excessive alcohol
• In later life, reducing social isolation, air pollution and vision loss.

Flavonoids, by lowering blood pressure and inflammation, fit into that plan.