February 21, 2006 – Generalized vitamin D deficiency could be one of the main causes of the significant increase in cardiovascular disorders worldwide. This is the conclusion reached by German researchers who have just published, in the British Journal of Nutrition1, the results of a synthesis of recent medical knowledge on the role of this vitamin.
If science has not yet identified the exact causes of the increase in the number of cases of cardiovascular disease in recent decades, the authors of this study put forward an explanation. This increase could be inversely proportional to the intake of vitamin D. The sedentary lifestyle of Western societies would lead to a decrease in vitamin D intake due to lack of exposure to sunlight, according to these researchers from the cardiothoracic surgery department. of the Ruhr University of Bochum, Germany.
“In the past,” they write, “80% or 90% of vitamin D intake came from the skin’s synthesis of this vitamin under the effect of exposure to UV rays. According to them, the modern way of life means that human beings are less and less exposed to these rays. This would result in a deficiency in vitamin D. Although it does not constitute a deficiency in the true sense of the term, this deficiency could, according to their hypothesis, constitute an important risk factor for suffering from cardiovascular disorders.
As reported by the researchers, the results of several epidemiological studies indicate that populations living in northern latitudes, where exposure to UV rays is lower than in the South, are generally more exposed to cardiovascular disorders. This would correspond to a decrease in the body’s reserves of vitamin D.
The increase in the number of hours spent indoors, whether at work or at home, as well as the systematic use of the automobile for the slightest trips, would help deprive the body of vitamin D which he needs. It has also been observed that the adoption of this sedentary lifestyle by the populations of the countries of the South goes hand in hand with a proportional increase in the incidence of cardiovascular disorders in these regions.
Researchers believe that this risk factor has been largely underestimated to date. Especially since food sources of vitamin D2 are relatively few, if we exclude foods artificially fortified with this vitamin.
The authors of the study report scientific data that highlights the essential role played by this nutrient. Vitamin D actually inhibits the excessive proliferation of smooth muscles in blood vessels, opposes the calcification of these vessels, lowers the production of pro-inflammatory cytokines, increases that of anti-inflammatory cytokines and helps to regulate blood pressure. Theoretically, all of these factors would prevent cardiovascular disorders.
While admitting that it is necessary to conduct several clinical trials to confirm this hypothesis, the researchers stress that the authorities should review urban land use planning so as to leave more room for pedestrians, and consider systematically fortifying certain foods with vitamin D.
Pierre Lefrançois – PasseportSanté.net
1. Zittermann A, Schleithoff SS, Koerfer R. Putting cardiovascular disease and vitamin D insufficiency into perspective, Br J Nutr, 2005 Oct; 94 (4): 483-92.
2. To find out which foods contain the most vitamin D, see our Top List.
