Too much vitamin D may cloud benefits

According to a recent study, in the U.S., obese older women, who take more than three times the recommended daily dose of vitamin D showed improvements in memory and learning but also had slower reaction times. The researchers hypothesised that slower reaction times may increase the risk of falling among older people.

The results of the study were published in Journals of Gerontology: Series A. The researchers used computers to assess the impact of vitamin D on cognitive function. They evaluated three groups of women between 50 and 70 years in a randomised controlled trial. One group took the recommended daily dose of 15 mcg of vitamin D each day for a year. Another group took more than three times and the third took nearly seven times.

The researchers found that memory and learning improved in the second group but not in the group that took the higher dosage. Meanwhile, the women’s reaction time showed a trend to be slower as dosage increased. “The slower reaction time may have other negative outcomes such as potentially increasing the risk of falling and fractures,” said senior study author Sue Shapses.