Most people know that vitamin D helps keep our bones healthy and strong. We usually get it from sunlight, some foods, or from supplements.
But in recent years, scientists have started looking at how vitamin D might also help the brain—especially as we get older.
A new study from Rutgers University gives us some new clues. Researchers studied a group of women between 50 and 70 years old. These women were either overweight or obese, and that’s important because extra body fat can change the way our bodies use vitamin D.
The scientists wanted to find out if different amounts of vitamin D would affect the women’s memory, thinking, and reaction time.
The women were split into three groups. Each group took a different amount of vitamin D every day for one year. One group took 600 IU (international units), which is the usual amount recommended for adults.
Another group took 2,000 IU. The third group took 4,000 IU, which is a high dose. All of the women were also encouraged to lose weight during the study.
After a year, the results were interesting. The group that took 2,000 IU of vitamin D each day had better memory and were better at learning new things. This shows that taking a little more vitamin D might help the brain remember and learn.
But there was a downside too. The same group, and especially the women who took the highest dose of 4,000 IU, had slower reaction times. That means they didn’t respond as quickly when something happened around them.
This could be dangerous for older people. Slower reactions might mean a greater chance of falling or getting hurt while walking, crossing streets, or avoiding things in their way.
Other studies have found similar results. People who take high doses of vitamin D—2,000 IU or more—might actually fall more often. So while vitamin D might help your brain in some ways, it could also make your body slower to react, which could cause new problems.
This raises big questions. What is the right amount of vitamin D for brain health? Should men and women take different amounts? Do slower reactions really lead to more falls? Scientists say we need more studies to answer these questions.
What we do know is that vitamin D, like many nutrients, is best when taken in the right amount. Too little might not help your brain or bones. Too much might bring side effects we don’t expect.
The good news is that vitamin D is just one part of staying sharp as we age. Eating a healthy diet—especially one like the Mediterranean diet, which includes lots of vegetables, fruits, whole grains, and healthy fats—can also help.
Foods with fiber, B vitamins, and antioxidants have also been linked to better brain function and a lower chance of dementia.
The Rutgers study, led by researcher Sue Shapses and published in The Journals of Gerontology: Series A, reminds us that when it comes to vitamins, more isn’t always better. Sometimes, the right amount is just enough.
If you care about nutrition, please read studies about 9 signs you have inflammation in your body. Could an anti-inflammatory diet help? and high-salt diet strongly changes your kidneys.
For more about diet, please read studies that fiber is your body’s natural guide to weight management and diet and nerve damage in diabetes: a novel insight.
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