For anybody with a loved one experiencing dementia or Alzheimer’s, news of prospective drug treatments failing or producing mixed results is a cause for concern.
But emerging evidence gives reasons for hope too, with research suggesting a common vitamin supplement may have a promising effect on patients with signs of early dementia, and it’s a cheap daily pill that’s available to anybody.
In a new study published in Sleep Medicine, scientists found daily intake of a vitamin D supplement was linked with a significant boost in cognitive test results for people with two hallmarks of early dementia: mild cognitive impairment (MCI) and sleep disturbances.
According to the scientists, it’s the first research analyzing the link between vitamin D supplementation and cognition in patients with these two key symptoms, but it’s worth noting that this is only a small observational study – and it doesn’t prove that vitamin D enhances cognitive performance.
Nonetheless, the findings add to growing evidence that vitamin D may protect brain health and help stave off dementia, in addition to seemingly offering benefits to aging processes, heart health, and depression, among many other conditions.
As we so often see with neurodegenerative diseases, taking action early may be crucial, researchers think.
“This may represent a critical window for intervention, when cognitive changes are emerging, but opportunities to support brain health may remain,” says sleep scientist Victoria Pak from Emory University in Atlanta, Georgia.
In the study, Pak’s team assessed 54 adults aged 50 or older, all of whom had diagnosed or suspected MCI, and showed signs of sleep disturbance.
The participants undertook the Montreal Cognitive Assessment (MoCA) to evaluate their levels of cognitive function, and two separate tests to measure their sleep quality, the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS).
Participants also reported their levels of vitamin D intake, and when the researchers compared their daily dosage against the cognitive and sleep measures, an interesting result stood out.
After accounting for potential confounding factors including age, sex, body mass index (BMI), vitamin D type, and education level, the researchers found participants who took a daily dosage of 5,000+ IU of vitamin D scored ~13 percent higher (3.78 points higher) on the MoCA cognitive test results compared with those who didn’t take vitamin D supplements.
People taking lower daily doses of vitamin D also scored nominally higher than participants who didn’t take daily vitamin D, but the lower-dose results were not statistically significant.
The association for 5,000+ IU held true regardless of whether the participants took vitamin D2 or vitamin D3, but it’s worth noting that 5,000+ IU is slightly above the maximum suggested daily intake of vitamin D, which is 4,000 IU, an amount generally considered to be the safe upper limit to avoid developing hypercalcemia.
For that reason, it’s important to realize that the key result here is not any kind of updated recommendation about how much vitamin D people should take – even if research is starting to show that doses between 4,000 and 6,000 IU may offer greater protection against some adverse health outcomes.
Related: One Common Vitamin Could Lower Toxic Alzheimer’s Proteins, Research Suggests
At this stage, this is only a preliminary finding from a small study, which the researchers say warrants further analysis in subsequent studies involving larger groups of participants.
While we have to remain cautious for now, it’s a great lead for scientists to investigate in future, especially since vitamin D is so inexpensive and readily available.
Once the science settles, we could have something really significant here.
“Identifying accessible and modifiable factors, such as vitamin D supplement intake, during the earlier stages of cognitive decline may become increasingly important,” Pak says, “particularly as rates of Alzheimer’s disease continue to rise.”
The findings are reported in Sleep Medicine.
