Vitamin D supplements could help prevent dementia, according to a recent study.

Researchers from Canada and the U.K. conducted a study with 12,000 participants to reveal the link between vitamin D supplements and dementia.

The results published Wednesday in the journal Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring showed that 4,637 participants who took vitamin D developed 40% less dementia than those who took no vitamin D.

The researchers observed 2,696 participants who developed dementia in 10 years, including 2017, who never took vitamin D supplements before being diagnosed with dementia, and 679 others who took a low dose of supplements.

Scientists from the University of Calgary's Hotchkiss Brain Institute and the University of Exeter said the average age of the participants was 71, and they were not diagnosed with dementia before the study.

"We know that vitamin D has the impact of reducing dementia in the brain, but the studies conducted so far had controversial results," research leader Zahinoor Ismail said.

He added that it is helpful to start taking vitamin D supplements before the cognitive impairment starts, as evidence shows.

According to the World Health Organization, dementia is caused by diseases and injuries affecting the brain, such as Alzheimer's or strokes. Worldwide, around 55 million people have dementia, with over 60% living in low – and middle-income countries.