Vitamin D Deficiency May Raise Dementia Risk, Testing 25-Hydroxy Levels Guides Treatment
Updated
Updated · Psychology Today · Jun 12
Vitamin D Deficiency May Raise Dementia Risk, Testing 25-Hydroxy Levels Guides Treatment
2 articles · Updated · Psychology Today · Jun 12
Summary
Vitamin D deficiency often goes unnoticed even in sunny climates, and the report says low levels may affect mood, memory and cognition because vitamin D acts more like a hormone in brain tissue.
Brain-related concern stems from observational studies and a 2024 meta-analysis linking lower vitamin D status to poorer cognitive outcomes and higher dementia risk, though the evidence does not prove causation.
Depression findings are more limited: a large 2020 randomized trial found long-term vitamin D3 did not prevent depression overall, while people who were deficient at baseline may benefit most from correction.
A 25-hydroxyvitamin D blood test is presented as the key next step, with diet and vitamin D3 supplements used when deficiency is confirmed because more supplementation is not automatically better.