It has been shown that deaths related to cardiovascular disease are more frequent in higher latitudes and during the winter months – when and where the sun rarely shines – and are less frequent at higher altitudes. Edward Giovannucci, M.D., Sc.D. (Harvard School of Public Health and Brigham and Women’s Hospital, Boston) and colleagues note that, “This pattern is consistent with an adverse effect of hypovitaminosis D [vitamin D deficiency], which is more prevalent at higher latitudes, during the winter and at lower altitudes.” Although there are most likely several reasons for these observations, researchers do know that vitamin D impacts the body in ways that affect the risk of heart attack and heart disease.
Giovannucci and colleagues reviewed the medical records and blood samples of 454 men between the ages of 40 to 75 who had non-fatal heart attack or fatal heart disease. Initial data collection occurred between January 1993 and December 1995, and patients were followed until January 2004. The researchers compared this first sample with records and blood samples of 900 living men who had no history of cardiovascular disease. Self-administered questionnaires were used to collect data on the diets and lifestyles of the men.
The main finding was that men who had a vitamin D level of 15 nanograms per milliliter of blood or less (vitamin D deficiency) had a higher risk of heart attack compared to those with 30 nanograms per milliliter of blood (vitamin D sufficiency).
“After additional adjustment for family history of myocardial infarction, body mass index, alcohol consumption, physical activity, history of diabetes mellitus and hypertension, ethnicity, region, marine omega 3 intake, low- and high-density lipoprotein cholesterol levels and triglyceride levels, this relationship remained significant,” write the researchers. Even men with intermediate vitamin D levels were found to have a greater risk of heart attack than those with sufficient levels.
The authors conclude their study by noting: “Vitamin D deficiency has been related to an increasing number of conditions and to total mortality. These results further support an important role for vitamin D in myocardial infarction risk. Thus, the present findings add further support that the current dietary requirements of vitamin D need to be increased to have an effect on circulating 25(OH)D [vitamin D] levels substantially large enough for potential health benefits.”
25-Hydroxyvitamin D and Risk of Myocardial Infarction in Men: A Prospective Study
Edward Giovannucci; Yan Liu; Bruce W. Hollis; Eric B. Rimm
Archives of Internal Medicine (2008). 168:1174 – 1180.
Written by: Peter M Crosta