Many people take Vitamin D supplements because they’ve heard it’s good for their bones, immune system, and overall health.
But a new study from Intermountain Health in Salt Lake City shows that the usual amount of Vitamin D we take might not be enough to protect our hearts.
For years, scientists have known that low Vitamin D levels are linked to a higher risk of heart attacks and strokes. But now, researchers are asking a big question: Are the current Vitamin D guidelines strong enough to really help our hearts? The answer might be no.
The U.S. currently recommends 600 to 800 International Units (IU) of Vitamin D per day. But in two recent studies, many patients needed much more—some even needed more than 10,000 IU per day just to reach healthy levels of Vitamin D in their blood.
Dr. Heidi May, an expert at Intermountain Health, says that earlier research didn’t use high enough doses of Vitamin D. That may be why some past studies didn’t show much benefit. In other words, if people aren’t taking enough Vitamin D, it’s no surprise they aren’t seeing big improvements in their health.
Another researcher, Viet T. Le, believes we need to stop using a “one-size-fits-all” approach. Everyone’s body is different, and some people may need much more Vitamin D than others to stay healthy. The key may be giving each person the right amount based on their own needs.
In one important study called the Target-D trial, researchers looked at people who had just had a heart problem, like a heart attack or chest pain. The goal was to raise their Vitamin D levels to more than 40 nanograms per milliliter—a level that the scientists thought was best for heart health.
What they found was surprising. Almost 90% of the people in the study needed extra Vitamin D. And many of them needed much higher doses than the official guidelines suggest. Even with these higher doses, it often took three to six months—or even longer—for people to reach their goal.
This research tells us that doctors and scientists may need to rethink how they use Vitamin D in treating and preventing heart problems. If most people aren’t getting enough from standard doses, then maybe the guidelines need to be updated. It also shows how important it is to treat each person as an individual.
Vitamin D is clearly important for our health, but taking the right amount matters even more. If you’re worried about your heart or your Vitamin D levels, talk to your doctor. They might suggest a blood test and a personalized plan to make sure you’re getting exactly what your body needs.
If you care about nutrition, please read studies about the best time to take vitamins to prevent heart disease, and vitamin D supplements strongly reduce cancer death.
For more information about nutrition, please see recent studies about plant nutrient that could help reduce high blood pressure, and these antioxidants could help reduce dementia risk.
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