Vitamin D Deficiency and Cardiovascular Disease: Understanding the Risks

Written by Grace Holden

Photo of the author Grace Holden

Introduction

Vitamin D deficiency is one of the most widespread nutritional deficiencies, affecting nearly one billion people worldwide. While most people know vitamin D as essential for calcium absorption and bone health, it plays a larger role. Recent research shows that vitamin D impacts heart health and blood vessel function. Studies suggest a strong link between low vitamin D levels and cardiovascular disease, especially hypertension, atherosclerosis, and heart failure. However, the exact nature of this connection and whether supplements help remain a topic of debate.

This article explores how vitamin D influences cardiovascular health, focusing on its role in blood pressure, arteries, and heart function.

What is Vitamin D, and Why Does It Matter?

Vitamin D, often called the “sunshine vitamin,” is unique because sunlight triggers its production in the skin. Many people don’t get enough sunlight, and their diets lack vitamin D-rich foods, like fatty fish, egg yolks, and fortified products. As a result, vitamin D deficiency is common, especially in regions with limited sun exposure or where people spend most of their time indoors.

Vitamin D is crucial for:

  1. Bone Health: It helps the body absorb calcium, builds strong bones, and prevents diseases like osteoporosis.
  2. Immune Function: It supports the immune system, helping fight infections.
  3. Heart and Blood Vessel Health: Research shows vitamin D impacts blood pressure, artery health, and heart muscle function.

How Vitamin D Affects Cardiovascular Health

Vitamin D receptors are found in the cells of the heart, blood vessels, and the smooth muscles around arteries. This discovery shows that vitamin D is involved in many cardiovascular processes:

  1. Regulating Blood Pressure: Research shows seasonal changes in blood pressure, with lower levels in the summer when vitamin D levels are higher. Low vitamin D is often linked to high blood pressure, a major cardiovascular risk factor.
  2. Preventing Atherosclerosis: Atherosclerosis is a buildup of plaque in arteries that can lead to heart attacks and strokes. Vitamin D helps reduce inflammation in blood vessels, which may prevent plaque buildup.
  3. Protecting Heart Muscle: Vitamin D is an anti-fibrotic agent, reducing heart scarring and helping prevent the thickening of heart muscle, a common issue in heart failure.

Vitamin D Deficiency and Risks of Cardiovascular Disease

Low vitamin D levels increase the risk of several cardiovascular conditions. Here’s how:

1. Hypertension (High Blood Pressure)

Vitamin D regulates blood pressure by reducing the activity of the renin-angiotensin-aldosterone system (RAAS), a hormone system that controls blood pressure. Low vitamin D levels may overactivated this system, leading to high blood pressure. Chronic high blood pressure can damage arteries, the heart, and organs, greatly increasing cardiovascular risks.

2. Atherosclerosis

In atherosclerosis, plaque builds up on artery walls, causing arteries to narrow and harden. This can reduce blood flow, leading to conditions like coronary artery disease and peripheral artery disease. Vitamin D’s anti-inflammatory properties may help prevent plaque formation. Studies show that people with low vitamin D often have high levels of inflammation, which can drive atherosclerosis.

3. Heart Failure

Heart failure happens when the heart becomes too weak or stiff to pump blood effectively. Vitamin D deficiency links to a higher risk of heart failure, as low levels can contribute to fibrosis (scarring) and hypertrophy (thickening) of the heart muscle. Animal studies suggest that vitamin D plays a protective role in preventing these damaging changes.

The Debate: Do Vitamin D Supplements Help?

Despite strong links between low vitamin D and cardiovascular disease, studies show mixed results on the benefits of supplements:

  1. Observational vs. Interventional Studies: Observational studies link low vitamin D with heart disease risk, but intervention studies show inconsistent results. When researchers gave people vitamin D supplements, the supplements did not always reduce cardiovascular events.
  2. Possible Reasons for Inconsistent Results: Many factors could explain these inconsistencies. Vitamin D supplements alone may not solve complex cardiovascular problems. Factors like diet, lifestyle, and existing health conditions also play roles. Vitamin D may not directly prevent heart disease but support overall cardiovascular health.

Who is Most at Risk for Vitamin D Deficiency?

Certain groups face higher risks for vitamin D deficiency, which may also increase their cardiovascular risks. These groups include:

  1. Older Adults: Aging reduces the skin’s ability to produce vitamin D.
  2. People with Limited Sun Exposure: Those living in colder climates, high latitudes, or who have jobs indoors are at risk.
  3. People with Darker Skin: Melanin, which gives skin pigment, reduces the skin’s ability to produce vitamin D from sunlight.
  4. People with Certain Medical Conditions: Conditions like obesity, kidney disease, or gastrointestinal disorders can lower vitamin D levels.

Should You Take Vitamin D Supplements for Heart Health?

While the exact role of vitamin D in heart disease prevention remains uncertain, keeping vitamin D levels within a healthy range is essential for overall well-being. For those with a known deficiency, supplements can bring levels back to normal and may indirectly support heart health. However, people with normal levels should avoid high doses of supplements solely for heart protection, as this may not provide the intended benefits and could even be harmful.

If you think you may have a deficiency, consult a healthcare provider for testing and a personalized dosage recommendation.

Key Takeaways: Vitamin D and Cardiovascular Health

Vitamin D deficiency is common, and low levels are often linked to higher risks of hypertension, atherosclerosis, and heart failure. While vitamin D’s role in heart health is significant, the benefits of supplements for preventing heart disease are still uncertain.

To protect your cardiovascular health, maintain healthy vitamin D levels through safe sun exposure, a balanced diet, and supplements if necessary. Remember, heart health depends on multiple factors, such as diet, exercise, and regular check-ups, which work together to protect your heart and blood vessels.

Conclusion

Vitamin D plays a vital role in bone and immune health and has been shown to influence cardiovascular health by helping to regulate blood pressure, supporting arteries, and protecting the heart muscle. Although more research is needed to confirm the benefits of vitamin D supplements for heart health, maintaining adequate levels is essential for overall wellness.

Anyone at risk of deficiency should consult a healthcare provider to consider testing and potential supplementation. By maintaining vitamin D levels and focusing on a heart-healthy lifestyle, you can take active steps toward reducing your cardiovascular disease risk.

Continue exploring our blog for more on heart health, vitamin D, and other wellness topics.

Keywords: Vitamin D deficiency, cardiovascular disease, heart health, hypertension, atherosclerosis, heart failure, vitamin D supplements, vitamin D and heart.

Source: Latic N, Erben RG. Vitamin D and Cardiovascular Disease, with Emphasis on Hypertension, Atherosclerosis, and Heart Failure. Int J Mol Sci. 2020 Sep 4;21(18):6483. doi: 10.3390/ijms21186483. PMID: 32899880; PMCID: PMC7555466.