Most people know that vitamin D helps keep bones strong, but a new study suggests it also affects the brain.
Researchers from Rutgers University looked at how vitamin D might help with memory and thinking speed in older women, especially those between 50 and 70 years old.
We get most of our vitamin D from sunlight. People who don’t spend much time outdoors can take it as a supplement. While it’s known for helping bones, scientists are now looking at how this vitamin may also support the brain, especially as we age.
In the study, the researchers focused on women who were overweight or obese. These women were put into three groups and given different amounts of vitamin D each day for a year.
One group took 600 IU, which is the standard recommended dose. Another group took 2,000 IU, and the last group took 4,000 IU. All of the women were also trying to lose weight, since past studies have shown that weight loss may improve how the brain works.
After one year, the women who took 2,000 IU of vitamin D every day showed the best results. They had better memory and were quicker at learning new things. But there was one downside: their reaction time—how fast they could respond to things—was a bit slower.
The women who took 4,000 IU each day had an even slower reaction time. This matters because slower reflexes can raise the risk of falls and injuries, which are serious concerns for older adults.
Other studies have also warned that taking more than 2,000 IU of vitamin D daily could make people more likely to fall. So even though vitamin D might help the brain, too much could hurt physical safety. The key is to find the right amount that helps without causing harm.
The study also suggests that men and women may need different vitamin D levels to protect both brain function and body balance, but more research is needed to know for sure.
Besides vitamin D, there are other ways to protect your brain as you age. Eating a healthy diet like the Mediterranean diet—which includes lots of vegetables, healthy fats, and lean meats—has been linked to better memory and a lower risk of memory loss. Foods rich in vitamin B, fiber, and antioxidants also help keep the brain healthy.
The study was led by Sue Shapses and published in The Journals of Gerontology: Series A. It gives us helpful information about how vitamin D may support memory, but it also reminds us that more is not always better. Getting the right balance is important.
If you care about nutrition, please read studies about the benefits of low-dose lithium supplements, and low calorie diets may help reverse type 2 diabetes.
For more health information, please see recent studies about the best and worst foods for high blood pressure, and time-restricted eating: a simple way to fight aging and cancer
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