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Member Research & Reports

Member Research & Reports

Rutgers: More Vitamin D May Improve Memory but Too Much May Slow Reaction Time

Overweight and obese older women who took more than three times the recommended daily dose of vitamin D showed improvements in memory and learning – but also had slower reaction times, according to a new study co-authored by Dr. Nancy Fielder, professor at the Rutgers School of Public Health.

These findings suggest that slower reaction times may increase the risk of falls among older adults.

The researchers, whose work is in The Journals of Gerontology: Series A assessed the impact of vitamin D on cognitive function, evaluating three groups of women between 50 and 70 years old in a randomized controlled trial. One group took the recommended daily dose of 600 international units (IU), equivalent to 15 micrograms, of vitamin D each day for a year. Another group took 2,000 IU per day and the third took 4,000.

The researchers found that memory and learning improved in the group that took 2,000 IU per day, but not in the group that took the higher dosage. Meanwhile, the women’s reaction time showed a trend to be slower at 2,000 IU daily and was significantly slower at the higher dosage.

Vitamin D – known for its importance for bone health – is obtained through sun exposure and some foods. Researchers have also found that vitamin D has a major impact on how the body, including the brain, functions.

Cognitive impairment and dementia are significant public health problems, especially with aging, the study notes. Evidence shows that vitamin D plays a role in cognition and the normal functioning of the central nervous system.

The study was led by Dr. Sue Shapses and co-authors include Ms. Monica Castle, Drs. L. Claudia Pop, Stephen J. Schneider, Yvette Schlussel, and Lihong Hao, all of Rutgers University, and Dr. Deeptha Sukumar, Drexel University.