A recent study from Rutgers University looked at how vitamin D affects brain function in older women.
Most people know that vitamin D is good for strong bones, but researchers are now learning that it may also impact memory, learning, and how quickly someone reacts.
Vitamin D comes from sunlight, food, and supplements. Many older adults take it to stay healthy, but scientists are still trying to figure out the best amount to take, especially as people age. In this study, researchers focused on overweight and obese women between the ages of 50 and 70.
The study lasted for one year. The women were divided into three groups based on how much vitamin D they took each day. One group took 600 international units (IU), which is the standard daily amount.
Another group took 2,000 IU, and the last group took 4,000 IU. Everyone in the study was also encouraged to lose weight because weight loss can help brain health, too.
The results showed that women who took 2,000 IU each day had better memory and learning skills than those who took 600 IU. This suggests that taking more vitamin D than the basic recommendation may help with thinking and remembering.
But there was also a surprise. Women who took 2,000 IU had slightly slower reaction times, and those who took 4,000 IU were even slower. Reaction time is important for older adults because slow reactions can increase the chance of falling. Falls can lead to broken bones and other serious problems.
Other research has already shown that taking more than 2,000 IU of vitamin D per day might raise the risk of falls. This new study supports that idea. It suggests that taking 4,000 IU daily could be risky for older adults, even if it helps memory.
The study raises new questions. Researchers still need to find out if slower reaction times actually lead to more falls. They also don’t know if men and women respond the same way to vitamin D. More studies are needed to figure out the safest and most helpful dose for everyone.
If you’re trying to keep your brain healthy, there are other things to consider besides vitamin D. For example, the Mediterranean diet, which includes fruits, vegetables, whole grains, and healthy fats, has been linked to better brain health.
Some studies also suggest that B vitamins and high-fiber foods can reduce the risk of dementia. Foods rich in antioxidants, like berries and nuts, may also help protect the brain as we age.
The Rutgers study was led by researcher Sue Shapses and published in The Journals of Gerontology: Series A. It reminds us that more vitamin D isn’t always better. Taking too much could slow your reaction time and increase your risk of falling.
If you take vitamin D supplements, it’s a good idea to talk to your doctor. They can help you find the right amount that supports your brain health without causing harm.
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