This year marks the 50th year of American Hearth Month. American Heart Month is a time to make people aware of the risks of heart disease and to take important steps to live a better and healthier life.
And what better way to reflect on the awareness month than on Valentine’s Day.
Each year, heart disease increases in prevalence in the United States. In a recent update from the American Heart Association, researchers found that roughly 83.6 million American adults have at least one type of heart disease. About 78 million have hypertension (high blood pressure), 15.4 million have coronary heart disease, and 5.1 million have heart failure.
To try and help prevent heart disease, there are some things you can do, including:
- Eating a healthy, low-sodium diet consisting of lots of fruits and vegetables
- Exercising regularly
- Limiting alcohol use
- Checking cholesterol levels often and working with your doctor
In addition to these classic risk factors, researchers are more and more interested if getting enough vitamin D might help prevent or help manage heart disease.
If you follow our blog, then you undoubtedly know that researchers are rigorously investigating the link between vitamin D and cardiovascular disease. You can see all of our blogs on the topic in the tag here: http://www.vitamindcouncil.org/tag/cardiovascular-disease/
To synthesize some of the things researchers are interested in vitamin D and heart health, researchers are interested in vitamin D’s role in:
- Renin angiotensin system (RAS) – The RAS is a hormone system that plays a major role in the regulation of blood pressure. An overactive RAS can increase blood pressure and increase your risk of hypertension. Studies have shown that vitamin D can directly lower expression of the RAS and therefore may reduce the risk of future hypertension. There have been some trials examining if vitamin D supplementation can lower blood pressure. Some trials show that it does, and some show that it doesn’t.
- Vascular smooth muscle cells (VSMC) – Researchers have found vitamin D receptors on the cells in the vascular smooth muscles. For reasons not fully understood yet, the body can produce too many new VSMCs which could lead to the formation of plaques in the arteries. Research has shown that through binding to these cells, vitamin D may be able to reduce the risk of overproduction of VSMCs and subsequent plaques.
- Insulin resistance – Common in those with type 2 diabetes and heart disease, insulin resistance is characterized by the body’s inability to recognize and use insulin. This can lead to elevated blood sugar levels, increased inflammation, and an increased risk of heart attack and stroke. Researchers have discovered vitamin D receptors on the pancreatic beta-cells. These beta-cells are the main driver in insulin production, and research has shown that vitamin D may be able to increase production of insulin by binding to these beta cells.
- Atherosclerosis – Atherosclerosis is characterized by the build-up of plaques in the arteries. These plaques often form when things like fat, cholesterol and calcium accumulate in the arteries. These plaques make it more difficult for blood to flow throughout the body and therefore increases the risk for things like heart attack and stroke. Past laboratory studies using human blood cells showed that the activated form of vitamin D suppressed uptake of cholesterol and macrophage activation, and diminished foam cell formation. Foam cells are immune cells that are sent to destroy fatty deposits in the blood vessels. High levels of deposits and plaques in blood vessels can lead to high amounts of foam cells, thus contributing to the development of atherosclerosis.
- Endothelial dysfunction – Vitamin D supplementation has been shown to improve endothelial dysfunction. Endothelial dysfunction is the continuous imbalance between dilating and constricting substances produced by the endothelium (the inner lining of blood vessels). This imbalance can be both a contributing factor and a symptom of conditions such as coronary artery disease, hypertension, and diabetes.
- Cytokines – Vitamin D supplementation has been shown to both reduce concentrations of the inflammatory cytokine tumor necrosis factor alpha (TNF-alpha) and increase concentrations of the anti-inflammatory cytokine interleukin 10 (IL-10). Normally, the heart doesn’t produce any TNF-alpha. However, in heart failure the heart does produce TNF-alpha which can lead to death of the heart muscle cells. Vitamin D may help by suppressing this damaging inflammation.
As you can see, research in vitamin D and heart health is an expanding and exciting field. Researchers are still trying to figure out how vitamin D exactly works and how effective it just might be in preventing various heart diseases. Heart disease is complex, and vitamin D may have many interconnecting roles in keeping the heart healthy.
Gardner, D. G. et al. Vitamin D and the Cardiovascular System. In Vitamin D: Third Edition by Feldman, Pike, Adams. Academic Press, 2011.
Sourij, H. & Dobnig, H. Vitamin D and Cardiovascular Disease. In Vitamin D: Third Edition by Feldman, Pike, Adams. Academic Press, 2011.
Towler, D. A. Vitamin D: Cardiovascular Effects and Vascular Calcification. In Vitamin D: Third Edition by Feldman, Pike, Adams. Academic Press, 2011.