A recent study from Rutgers University explored how vitamin D affects brain function in older adults.
Many people know vitamin D helps keep bones strong, but scientists are now studying how it may also affect memory, learning, and reaction speed. Vitamin D comes from sunlight, certain foods, and supplements, and many older adults take it daily to stay healthy.
In this study, researchers focused on overweight and obese women aged 50 to 70. The goal was to see how different daily amounts of vitamin D influenced their brain performance over time.
The study lasted one year, and the women were divided into three groups. One group took 600 IU per day, which is the usual recommended amount. The second group took 2,000 IU daily, and the third group took 4,000 IU daily. All participants were also encouraged to lose weight because weight loss can affect brain health.
The researchers found that women who took 2,000 IU daily showed better memory and learning compared to those who took only 600 IU. However, the study also revealed an unexpected result.
The women taking 2,000 IU had slightly slower reaction times, and those taking 4,000 IU had even slower responses. Reaction time is important for older adults because slower reactions can increase the risk of falls, which may lead to serious injuries.
Previous studies have suggested that very high doses of vitamin D might increase fall risk. This new study supports that concern and suggests that taking 4,000 IU daily may be too much for some older people.
Scientists still need more research to understand whether slower reaction times directly lead to more falls and whether men and women respond differently to vitamin D.
The findings remind us that vitamin D has benefits, but more is not always better. Finding the right balance may help protect memory while avoiding unwanted side effects. If you take vitamin D supplements, it may be wise to speak with your doctor about the best amount for your age and health.
If you care about nutrition, please read studies about the harm of vitamin D deficiency you need to know, and does eating potatoes increase your blood pressure?
For more information about health, please see recent studies about unhealthy habits that may increase high blood pressure risk, and results showing MIND diet may reduce risk of vision loss disease.
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