New research reveals that low levels of folate, also known as vitamin B9, is linked to an increased risk for dementia and death.

The large-scale study, published online in the journal Evidence Based Mental Health, found that older adults who were deficient in folate were 68% more likely to be diagnosed with dementia and nearly three times more likely to die from any cause than those with normal levels of the B vitamin.

According to SCIENMAG, about 1 in 5 older adults may be deficient in folate, which can negatively affect cognition and nerve signaling in the brain, potentially leading to dementia. As a result of their new findings, researchers believe older adults should be screened regularly with a blood test to monitor for deficiencies.

To conduct the study, researchers analyzed the medical records of 27,188 men and women, between the ages of 60 and 75, with no previous history of dementia. Over a four-year period, the records were monitored for any diagnosis of dementia or death.

About 3,418, or 13%, of the participants were folate deficient. Among those who were folate deficient, the incidence of dementia was 7.96 per 10,000 person years and death from any cause was estimated 19.20 per 10,000 person years.

This contrasts to the estimated dementia rate of 4.24 and death rate from any cause of 5.36 of death per 10,000 person years among those who were not folate deficient.

The researchers accounted for any influential factors that could have interfered with the results, including diabetes, cognitive decline, depression, vitamin B12 deficiency, smoking, and folic acid supplements.

According to Bel Marra Health, the folate-deficient were 68% more likely to be diagnosed with dementia and nearly three times more likely to die from any cause. Although this was an observational study and did not look for cause-and-effect, the researchers believe folate deficiency may raise homocysteine levels, resulting in an increase in vascular risk of dementia.

Elevated homocysteine levels can also compromise the DNA repair of neurons, which make them more vulnerable to oxidative damage that triggers brain-cell aging.

Anat Rotstein from the Icahn School of Medicine at Mount Sinai in New York City and his colleagues said that their research provided evidence that there could be a causative effect, and not just an association, between low levels of folate and increased risk for dementia and all-cause mortality.

"Serum concentrations of folate may function as a biomarker used to modify the risks of dementia and mortality in old age," the authors wrote, according to SCIENMAG. "The implications for public health appear to be to reliably monitor serum concentrations in older adults and treat deficiency for preventative measures and/or as a part of implemented therapeutic strategies while regularly reviewing patients’ clinical outcomes."