Dementia is a group of symptoms associated with the ongoing decline of brain function.
More common among older people, it can result in memory loss, personality changes and mobility problems.
Although dementia can be unavoidable in some cases, it is actually possible to lower your risk of developing the condition.
In fact, scientists believe 40 percent of dementia cases could be prevented through factors such as diet, exercise, weight and blood pressure.
One expert spoke to Express.co.uk about how a certain supplement could be key when it comes to protecting your brain in later life.
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Patrick Holford, nutritionist, mental health expert and director of Food for the Brain, recommended upping your intake of omega-3 fatty acids.
More specifically he advocated for a type of omega-3 called docosahexaenoic acid (or DHA) which is naturally found in cold-water fatty fish.
He explained: "There is no brain of any animal that is not made primarily out of the omega-3 fat DHA, which is found in oily fish.
"Half of the entire 'membrane' through which all signals happen, in other words the talking and listening of brain cells, is made of DHA. So, without sufficient DHA all thinking slows down.
"Depression, ADHD, schizophrenia, autism and dementia are just a few of the associated conditions, but also eye problems, failing eyesight, dry skin, excessive thirst are symptoms of deficiency."
Mr Holford said: "Even eating one, two or, as we recommend, three servings of fish a week, with at least two being oily fish, doesn't get you to an optimal intake.
"You need to supplement omega-3 fish oil on top of this. A recent study of almost 5,000 people in the UK's Biobank shows that dementia risk drops by nine percent in those supplementing fish oils."
He warned: "There's no omega-3 DHA in a vegan diet. Vegetarian foods, such as chia, flax seeds and dark green veg do contain another form of omega-3 (ALA or alpha-linolenic acid) but less than five percent is converted into DHA.
"Fortunately, you can buy vegan DHA supplements that derive DHA from seaweed or algae."
Multiple studies have linked omega-3 and brain function.
One, published in Nutrients journal in 2022, showed that people with a higher blood DHA level were 49 percent less likely to develop Alzheimer's disease compared to those with lower levels.
In a separate paper, published in the European Journal of Clinical Nutrition in 2016, participants consumed different omega-3 polyunsaturated fatty acids including DHA and underwent cognitive testing.
"We found statistically significant associations between serum EPA, DPA and DHA and better performance in the trail making test and the verbal fluency test," it said.
"The individual associations with EPA and DHA were similar with the findings with EPA, DPA and DHA, although the associations with DHA were stronger."
Higher serum long-chain omega-3 PUFA concentrations were associated with better performance on neuropsychological tests of frontal lobe functioning in older men and women.
Common symptoms of dementia include:
If you think you or someone you know could have dementia you should speak to a GP.