September 25, 2012
Low Vitamin D Heightens Heart Attack Risk
Connie K. Ho for redOrbit.com — Your Universe Online
According to the World Health Organization (WHO), 17 million people die from heart disease every year. With this staggering statistic, it is no wonder that heart disease is one of the leading causes of death for adults around the globe.
In order to better understand heart disease, researchers from the University of Copenhagen and Copenhagen University Hospital went about studying vitamin D. The group of investigators recently discovered that vitamin D deficiency is related to increased risk of heart attacks and early death.
In the past, low levels of vitamin D have been associated with weak bone health. To target this issue, various population studies were initiated and scientists found that iron deficiency is connected to a heightened risk of ischemic heart disease, which is related to issues like heart attacks. Other studies on the effects of low levels of vitamin D have shown an elevated risk of high blood pressure; high blood pressure is also known to be a cause of heart disease. In particular, the most recent study included over 100,000 participants of Danish heritage and was recently featured in the journal Arteriosclerosis, Thrombosis and Vascular Biology.
"We have now examined the association between a low level of vitamin D and ischemic heart disease and death in the largest study to date. We observed that low levels of vitamin D compared to optimal levels are linked to 40% higher risk of ischemic heart disease, 64% higher risk of heart attack, 57% higher risk of early death, and to no less than 81% higher risk of death from heart disease," remarked Dr. Peter BrÃ¸ndum-Jacobsen, a researcher with the Clinical Biochemical Department at Copenhagen University Hospital, in a prepared statement.
Two methods were utilized in the research project. In one method, the researchers looked at the 5 percent lowest levels of vitamin D in comparison to the 50 percent highest levels of vitamin D. The higher risk of vitamin D deficiency was observed in the comparison. The researchers believed that this method helped prevent bias in the study.
In another method, data was pooled from the Copenhagen City Heart Study, where scientists measured the levels of vitamin D in blood samples from 1981 to 1983 and then continued to complete follow-up with the volunteers until this year. Moving forward, the researchers hope to identify whether the link between iron deficiency and heart disease is a valid causal relationship.
"With this type of population study, we are unable to say anything definitive about a possible causal relationship. But we can ascertain that there is a strong statistical correlation between a low level of vitamin D and high risk of heart disease and early death,” noted BÃ¸rge Nordestgaard, a clinical professor at the Faculty of Health and Medical Sciences at the University of Copenhagen, in the statement. “The explanation may be that a low level of vitamin D directly leads to heart disease and death. However, it is also possible that vitamin deficiency is a marker for poor health generally."
For those who are concerned about their vitamin D levels, vitamin D can be obtained through exposure to sunlight or vitamin D supplements. Experts at the University of Copenhagen note that the correct amount of sunlight for the body corresponds to approximately five to 30 minutes of sunlight on the arms, neck, and head various times in the week. However, in countries where sunlight exposure is low during the fall and winter months, it is important for individuals to seek other sources of vitamin D.
"The cheapest and easiest way to get enough vitamin D is to let the sun shine on your skin at regular intervals. There is plenty of evidence that sunshine is good, but it is also important to avoid getting sunburned, which increases the risk of skin cancer,” concluded BÃ¸rge Nordestgaard, who also serves as a senior physician at Copenhagen University Hospital, in the statement. “Diet with a good supply of vitamin D is also good, but it has not been proven that vitamin D as a dietary supplement prevents heart disease and death."