Vitamin D levels linked to better brain health

FORGET brain training, crosswords and puzzles, there’s a much easier way to increase cognitive function and stave off dementia — and it’s free too.

FORGET brain training, crosswords and puzzles — improving your mind could be as simple as getting a daily dose of sunlight.

Melbourne University researchers have found older women who have adequate vitamin D levels have better attention, cognitive flexibility and working memory.

Dr Alicia Goodwill studied 252 participants aged 55-67 from the Women’s Healthy Ageing Project to investigate the association between midlife vitamin D and cognition in Australian women.

The ‘slip slop slap’ message is still important, but just a few minutes of sun a day is required to get enough vitamin D. Picture: iStock

The 10-year observational study, published in Maturitas, found that middle-aged women who had vitamin D levels of more than 25 nanomoles per litre had better executive brain function.

It also identified a potential midlife window where ideal levels of vitamin D could protect against some types of cognitive decline.

Memory did not appear to be affected by vitamin D levels in the study.

This is because the women in the research pool were middle aged and decline in memory is generally not detectable until women reach their seventies, Dr Goodwill said.

Other research has identified type 2 diabetes, hypertension, obesity, smoking, depression, physical inactivity, and low cognitive stimulation or low education as dementia risk factors.

Now vitamin D has emerged as a prevention measure, she says.

“We’re not saying it’s a magic bullet or the magic sunshine. It’s one potential factor.” She said.

Modern lifestyles that involve long hours indoors working at desks, lots of screen time and less active transport all make it hard to get adequate vitamin D form the sun.

A number of studies have found many Australians are deficient in vitamin D particularly coming out of winter months.

Adequate vitamin D levels results in better attention, cognitive flexibility and working memory in older women. Picture: iStock

Exposure to the sun can cause skin cancer so it is important not to overdo it.

Only a small amount of sun exposure, just a few minutes a day, is required to get enough vitamin D.

Combining small amounts of sunshine with light exercise such as a walk, gardening or putting out the washing is an effective way to obtain sufficient amounts of vitamin D, says Dr Goodwill.

“Exercising outdoors is a great way to encourage people to get enough vitamin D, and given exercise also has positive effects for our brain health, this is an added benefit,” she says.

The ‘slip slop slap’ message is still important and the need for sun exposure for vitamin D synthesis needs to be carefully balanced with the risk of sunburn and skin cancers, she said.

There is not yet enough strong evidence that supplementation with vitamin D pills improves cognitive performance, or prevents cognitive decline or dementia, she said.

University of Melbourne Neurologist Professor Cassandra Szoeke says the latest results suggest optimal vitamin D in midlife may be an important target to slow cognitive ageing.

However, the only way to confirm such a cognitive benefit would be a randomised controlled trial where half of a vitamin D deficient cohort was administered vitamin D and the other half not was not, to see which had better outcomes but this could take decades.

“The earlier we are aware and modify lifestyle factors that are linked to cognitive health, the better and it is never too late to make positive changes to our health,” Professor Szoeke said.