Daily dose of vitamin D could reduce the risk of early-onset dementia

Vitamin D
Vitamin D

Taking daily vitamin D supplements and living a healthy lifestyle could reduce the risk of developing early-onset dementia, a study suggests.

British scientists have found for the first time that the risk of the disease, which sees dementia symptoms start before 65 years of age, can be reduced. It was previously thought the disease was caused solely by genetics and there was nothing people could do to lower their risk

However, according to an analysis, vitamin D deficiency, depression and a history of stroke can all increase the risk of early-onset dementia, while alcohol abuse, social isolation, hearing impairment and heart disease also increase the risk.

The NHS recommends everyone over the age of four take a daily vitamin D supplement of 10 micrograms if they are often inside or not exposed to sunlight.

The body makes vitamin D following exposure to the sun and people with darker skin can struggle to make as much as people with lighter skin

University of Exeter researchers found 15 lifestyle and health-related factors that can lower the risk of developing the condition. Most are modifiable, the scientists said, and are the same things which also increase the risk of normal dementia.

The study published in JAMA Neurology, analysed data from more than 350,000 people enrolled in the UK Biobank project and found a total of 485 cases of young-onset dementia.

Dementia before the age of 65 is classed as “young-onset dementia” and it is a condition that affects over 70,000 people in the UK.

‘Healthy drinker effect’

“There is still much to learn in our ongoing mission to prevent, identify, and treat dementia in all its forms in a more targeted way,” said study author Professor David Llewellyn.

“This is the largest and most robust study of its kind ever conducted. Excitingly, for the first time, it reveals that we may be able to take action to reduce the risk of this debilitating condition, through targeting a range of different factors.”

Dr Leah Mursaleen, Head of Clinical Research at Alzheimer’s Research UK, which co-funded the study, said: “This pioneering study shines important and much-needed light on factors that can influence the risk of young-onset dementia.

“This starts to fill in an important gap in our knowledge. It will be important to build on these findings in broader studies.”

The study found that alcohol abuse was a risk factor for young-onset dementia, but those who did not drink at all were at higher risk than those who were moderate or heavy drinkers.

However, the researchers attribute this to the “healthy drinker effect” which is a phenomenon where people who drink alcohol tend to be healthier overall than those who do not.

The scientists called this finding “complex” and urged caution in interpreting the results as heavy alcohol consumption reduces the risk of dementia.

One of the modifiable factors was social isolation, with loneliness known to be a risk factor for dementia as it can lead to cognitive decline which is often a precursor to the disease.

A study published on Tuesday in JAMA Network Open found that for people living alone, having a pet may help reduce the risk of dementia by alleviating some of the loneliness.

Scientists found that people who are over 50 and live alone have a slower rate of cognitive decline, better memory and superior talking skills as they age if they have a pet.

The link was not seen in people who lived with others, indicating human companionship is stronger than that of a cat or dog.

“These findings suggest that pet ownership may be associated with slower cognitive decline among older adults living alone,” the study authors from Sun Yat-sen University, China, write in their study.

“If randomised clinical trials confirm our findings, pet ownership may help in slowing cognitive decline and preventing dementia,” they add.

Around one in three people in the UK live alone and loneliness has been linked to increased stress levels, health issues and early death.

Cognitive decline is a telltale symptom of early-stage dementia and preventing it is a key goal of scientists. Puzzles and brain activities are one way, as is physical exercise, but loneliness is a known risk factor for cognitive decline and subsequently dementia.

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