New research from Intermountain Health in Salt Lake City is raising big questions about whether today’s Vitamin D recommendations are truly enough to protect the heart.
Many people know that Vitamin D is important for bone health, but scientists have also found strong links between low Vitamin D levels and a higher risk of heart attacks, strokes, and other serious heart problems.
Because of this, Vitamin D has received a lot of attention in recent years. However, the new findings show that the standard daily dose recommended in the United States may not be high enough for many people, especially for those who want to improve their heart health.
In the United States, adults are advised to take 600 to 800 International Units (IU) of Vitamin D daily. But the new studies from Intermountain Health suggest that this amount may not be nearly enough for many patients.
In fact, some people in the studies needed more than 10,000 IU a day to reach what researchers believe are “optimal” Vitamin D levels. These results surprised even the scientists themselves, because the difference between the standard dose and the dose many people actually needed was extremely large.
According to Heidi May, PhD, an epidemiologist at Intermountain Health and one of the lead researchers, many older studies may have reached the wrong conclusions because they used Vitamin D doses that were far too low.
If patients in those earlier studies were not given enough Vitamin D, then the studies may have missed the supplement’s real benefits. Dr. May explained that incorrect dosing can create misleading results, because patients’ Vitamin D levels never reached the range that could show meaningful improvements in heart health.
Another researcher, Viet T. Le, DMSc, PA-C, also emphasized that Vitamin D treatment needs to be personal. Every person absorbs and uses Vitamin D differently. Some people may only need a small dose, while others may need several times more. He explained that this makes a “one-size-fits-all” approach unhelpful, especially for people recovering from heart conditions.
One of the most important parts of this research comes from the Target-D clinical trial. This trial included patients who had recently experienced a major heart-related event, such as a heart attack. The goal was to raise their Vitamin D levels to more than 40 nanograms per milliliter, which the researchers considered an optimal level.
The results showed that nearly 90 percent of participants needed Vitamin D supplements to reach this goal. Many of them required doses far higher than the usual recommendation. Even with these higher doses, it often took three to six months—sometimes longer—for patients to reach the target level.
This finding suggests that Vitamin D works slowly in the body and that low levels may take a long time to correct. This may help explain why previous clinical trials struggled to show strong results: patients may not have been given enough Vitamin D or enough time to reach therapeutic levels.
These discoveries have important implications for future research. One major takeaway is that scientists may need to rethink how they design Vitamin D studies.
If the goal is to understand how Vitamin D affects heart health, then future trials must make sure that participants actually reach optimal Vitamin D levels. Otherwise, the results may not reflect the true potential of the supplement.
The research also highlights the increasing importance of personalized medicine. Instead of recommending the same dose for everyone, doctors may need to consider individual factors like age, weight, health conditions, and existing Vitamin D levels when deciding how much a person should take.
Personalized treatment may be especially important for people who are already at high risk for heart problems or who have recently experienced a cardiovascular event.
Overall, the findings from Intermountain Health suggest that Vitamin D supplementation needs to be more intentional and more carefully tailored to each person.
This could mean rethinking current dosing guidelines and offering more personalized treatment plans to help patients reach and maintain healthy Vitamin D levels. With heart disease remaining one of the leading causes of death worldwide, improving Vitamin D treatment could be an important step toward better heart health for many people.
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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