High-Dose Vitamin D May Improve Cognition More Than Low-Dose Vitamin D
Vitamin D deficiency has been associated with dementia and cognitive decline, but supplements may help. In a study of 82 healthy individuals with low vitamin D levels, high-dose vitamin D supplements (4000 IU/day) improved visual/nonverbal memory more than did low-dose vitamin D supplements (400 IU/day) over 18 weeks.
The 2017 study took place in Canada, where short winter days can make it more difficult to get sufficient levels of vitamin D from sunlight. The higher-dose supplements raised blood levels of vitamin D compared with the lower-dose supplements.
Those who received the higher doses performed better at tests of visual memory such as the Pattern Recognition Memory Task and the Paired Associates Learning Task, but their performance on tests of verbal memory was not significantly different from those in the lower-dose group. This suggests that higher vitamin D levels are particularly important to visual/nonverbal memory.
The study by Jacqueline A. Pettersen was published in the journal Experimental Gerontology.
