Scientists have spent years trying to understand why some people experience a faster decline in memory and thinking than others.
While age remains the biggest risk factor, growing attention is being paid to everyday habits that could influence brain health long before dementia develops.
A new study from Emory University, published in Sleep Medicine and reported by ScienceDaily, adds another piece to that puzzle by examining vitamin D.
Looking beyond bone health
Vitamin D is best known for supporting healthy bones and muscles, but researchers have increasingly explored whether it also affects the brain.
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Previous research has linked low vitamin D levels with poor sleep, while sleep disturbances themselves have been associated with a greater risk of cognitive decline.
To investigate whether these factors might be connected, researchers focused on a group considered especially vulnerable: older adults with both mild cognitive impairment and persistent sleep problems.
What the study found
The study included 54 participants who completed cognitive testing while also reporting their vitamin D supplement use.
After comparing the results, researchers found that those taking at least 5,000 IU of vitamin D each day achieved cognitive scores that were more than 13% higher than participants who did not take the supplement.
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The association was not seen among people taking lower daily doses. Researchers also found no meaningful difference between vitamin D2 and vitamin D3, suggesting both forms were linked to similar outcomes.
Key findings:
- Higher vitamin D intake was associated with better cognitive test scores.
- The study involved older adults with mild cognitive impairment and sleep disturbances.
- Lower doses were not linked to the same benefit.
- Vitamin D2 and D3 showed similar results.
- The findings represent an association rather than proof of cause and effect.
An early window for research
The researchers believe the earliest stages of cognitive decline may offer an important opportunity to study lifestyle factors that could help support brain health.
However, they stress that the findings should not be interpreted as evidence that vitamin D prevents dementia or improves memory.
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Instead, the results provide a direction for future clinical research. Larger studies will be needed to determine whether vitamin D plays a direct role in slowing cognitive decline or whether the observed relationship is influenced by other health and lifestyle factors.
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This article is made and published by Mie Hermansen, who may have used AI in the preparation.