Most people know that vitamin D helps keep bones strong. We can get vitamin D from sunlight, food, or supplements. But now, scientists are learning that it may also help the brain, especially as we get older.
A new study from Rutgers University looked at how vitamin D affects brain health in women between the ages of 50 and 70. All the women in the study were either overweight or obese, which matters because body fat can affect how the body uses vitamin D.
The women were split into three groups. One group took 600 IU (international units) of vitamin D each day. This is the amount usually recommended for adults. Another group took 2,000 IU, and the last group took 4,000 IU, which is a high dose. The study lasted for one year, and the women were also encouraged to lose some weight during that time.
The results were surprising. Women who took 2,000 IU of vitamin D each day had better memory and were able to learn new things more easily. This shows that taking a slightly higher dose of vitamin D may help the brain.
But there was also a downside. The same group — and especially the women who took the highest dose of 4,000 IU — had slower reaction times. That means they were not as quick to respond to things happening around them.
This can be dangerous for older adults. Slow reactions can increase the risk of falls or injuries, such as when walking, crossing a street, or trying to avoid a hazard.
Other studies have found similar results. People who take high doses of vitamin D may actually fall more often. So even though higher doses might help memory, they could also make it harder for the body to stay balanced and respond quickly.
This raises some important questions. How much vitamin D is actually good for us? Should men and women take different amounts? And do slower reactions really lead to more falls? Researchers say we need more studies to find clear answers.
Still, this study gives us something to think about. Vitamin D is important, but we need to be careful not to take too much. Getting the right amount is key. Too little might not help the brain or bones. Too much might cause other problems.
The good news is that vitamin D is just one part of staying healthy. Eating well is also important. A diet full of fruits, vegetables, whole grains, and healthy fats — like the Mediterranean diet — can help protect the brain. Nutrients like fiber, B vitamins, and antioxidants also support brain health and may lower the risk of dementia.
The Rutgers study, led by researcher Sue Shapses and published in The Journals of Gerontology: Series A, reminds us that more is not always better. The best results may come from getting just enough — not too little, not too much.
As we get older, we can protect our brain health with a few simple steps: eat healthy, stay active, and take only the amount of vitamin D that our bodies truly need.
If you care about nutrition, please read studies about the power of beetroot juice, and the risks of mixing medications with dietary supplements.
For more health information, please see recent studies about how to boost iron intake: natural solutions for anemia, and results showing vitamin K may lower your heart disease risk by a third.
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