Low vitamin D levels may increase risk of heart disease

According to a new Danish study, low vitamin D concentrations in the blood seem to be associated with a significantly higher risk of heart attack and early death.

To investigate a potential link between vitamin D levels and the incidence of heart disease and mortality, the researchers measured 25-hydroxyvitamin D – 25(OH)D – concentrations in blood samples from 10,170 wo-men and men and documented cases of heart disease and premature death for an average of 29 years (1). In addition to this, a meta-analysis, including 18 studies investigating the risk of ischemic heart disease and 17 studies looking at vitamin D and early death, was performed. The study results showed that low levels of vitamin D (less than 15 nM vitamin per liter serum) in comparison to healthy levels (more than 50 nmol/liter) were linked to a 40% higher risk of ischemic heart disease, a 64% higher risk of heart attack, a 57% higher risk of early death, and an 81% higher risk of death from heart disease. The meta-analysis showed that the risk of ischemic heart disease and early death were increased by 39% and 46% for participants with the lowest 25(OH)D levels versus those with the highest concentrations.

The researchers noted that the findings of this population study can not determine anything definitive about a possible causal relationship. However, they added that the results indicate a strong statistical correlation between a low level of vitamin D and a high risk of heart disease and early death. An explanation may be that a low vitamin D level leads directly to heart disease and death, or that vitamin D deficiency is a marker for poor health in general. Results from several earlier population studies have already indicated that a low blood vitamin D concentration may be linked to a higher risk of ischemic heart disease, while other studies have shown that vitamin D deficiency may increase blood pressure.

1. Brøndum-Jacobsen, P. et al. 25-Hydroxyvitamin D Levels and Risk of Ischemic Heart Disease, Myocardial Infarction, and Early Death: Population-Based Study and Meta-Analyses of 18 and 17 Studies. Arteriosclerosis, Thrombosis and Vascular Biology. Published online September 2012.