It’s known that deaths from heart attack occur more frequently in higher latitudes and in the winter months. To find out why, Harvard researchers reviewed medical records and blood samples of 454 men who had non-fatal heart attack or fatal heart disease and compared them with samples from 900 living men with no history of heart disease. Those with low levels of vitamin D – common in winter months – were more likely to have a heart attack than those with higher levels.
Source: Archives of Internal Medicine (2008). 168[11]:1174 – 1180
