Heart disease is the number one cause of death among older adults around the world. As people age, their risk of heart problems such as heart failure, heart attacks, and circulation issues increases.
At the same time, many older adults are found to have low levels of vitamin D in their bodies. Vitamin D is often called the “sunshine vitamin” because our skin makes it when we are exposed to sunlight.
It is well known for helping keep bones strong, but for many years scientists have also wondered whether it plays a role in keeping the heart healthy.
Several earlier studies noticed that people with low vitamin D levels were more likely to develop heart disease. These findings led many people to believe that taking vitamin D supplements could protect the heart. As a result, vitamin D pills became very popular, especially among older adults who want to stay healthy.
However, noticing a link between low vitamin D and heart disease does not necessarily mean that vitamin D is the cause. It is possible that people with low vitamin D share other habits or conditions that increase their risk of heart problems.
To better understand this question, researchers at Beth Israel Deaconess Medical Center in the United States carried out a careful and well-controlled study.
Instead of simply observing people, they tested what actually happens when older adults take vitamin D supplements for a long period of time. The goal was to see whether higher doses of vitamin D could reduce signs of stress or damage in the heart.
The researchers focused on two special proteins found in the blood. These proteins are commonly used by doctors to check whether the heart is under strain or not working as well as it should.
Higher levels of these proteins usually suggest a higher risk of future heart problems. If vitamin D truly protects the heart, then taking supplements should lower the levels of these proteins over time.
The study used data from a large project called the Study to Understand Fall Reduction and Vitamin D in You, also known as the STURDY trial. This study was supported by the National Institute on Aging and ran from 2015 to 2019. It included adults aged 70 and older who had low vitamin D levels at the beginning of the study.
Participants were randomly placed into four groups and given different daily doses of vitamin D3, ranging from a low dose to a very high dose. Neither the participants nor the researchers knew who was receiving which dose until the study ended, which helps ensure fair and reliable results.
Blood samples were collected at the start of the study and several times over the following two years. The researchers carefully measured the heart-related proteins in each sample.
At the beginning, people with lower vitamin D levels did tend to have higher levels of one of these heart stress proteins. This supported earlier observations that low vitamin D and heart risk are connected.
However, the most important finding came later. After months and even years of taking vitamin D supplements, there was no meaningful drop in the heart-related proteins. This was true for people taking low doses and for those taking very high doses. The supplements did not improve these heart markers over time.
The results were also consistent across many different groups of people. Age, sex, race, and existing health problems such as high blood pressure or diabetes did not change the outcome. Vitamin D supplements simply did not reduce signs of heart strain in these older adults.
The researchers explained that this does not mean vitamin D is unimportant for health. It is still essential for bone strength and overall well-being. However, the findings strongly suggest that vitamin D supplements alone are not an effective way to prevent heart disease.
One possible explanation is that low vitamin D levels may be a sign of other lifestyle factors. For example, people who spend less time outdoors may get less sunlight, have lower vitamin D, and also be less physically active, which is known to affect heart health.
In the end, this study adds strong evidence that taking vitamin D supplements does not protect the heart, even in people who start out with low vitamin D levels.
For heart health, focusing on proven habits such as regular physical activity, balanced nutrition, and managing blood pressure may be more helpful. Scientists continue to study what truly links vitamin D and heart disease, but for now, vitamin D supplements should not be seen as a solution for preventing heart problems.
If you care about heart disease, please read studies that herbal supplements could harm your heart rhythm, and how eating eggs can help reduce heart disease risk.
For more health information, please see recent studies that apple juice could benefit your heart health, and results showing yogurt may help lower the death risks in heart disease.
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