Known for its benefits to bones and skin, vitamin D may also reduce the risk of cardiovascular events. A recent study by researchers in Australia reveals that monthly vitamin D supplements may even prevent heart attacks in people over 60.
This is not the first time scientists have probed the effects of vitamin D on cardiovascular health but, until now, there has been no evidence of a potential link between the two. This new research is the largest trial ever carried out on the subject.
The Australian researchers set out to determine whether monthly vitamin D supplementation in older people could have an impact on the rate of cardiovascular events and, more specifically, on the rate of heart attacks and strokes.
Published in the British Medical Journal (BMJ), the study involved 21,315 Australians aged between 60 and 84, who received either a dose of oral vitamin D or a placebo at the beginning of each month, for up to five years.
In the end, more than 80% of participants claimed to have taken at least 80% of the suggested doses throughout the study period.
The researchers then cross-referenced and analysed data from these participants, looking into hospital admissions and deaths, to determine whether they had suffered heart attacks and strokes or undergone coronary revascularisation.
Lower heart-attack rate
They found that the rate of major cardiovascular events was 9% lower in the vitamin D supplement group, corresponding with 5.8 fewer events per 1,000 participants.
More specifically, the rate of heart attack was 19% lower in the vitamin D group than in the placebo group, and the rate of coronary revascularisation was 11% lower.
On the other hand, the scientists noted no difference in stroke rates.
It’s important, however, to bear in mind the limitations of this study: the researchers point out that the effects appeared to be more convincing in participants who, at the start, were already receiving treatment designed to reduce the risk of cardiovascular events, such as statins.
They also mention that the difference in absolute risk was small between the two groups, although the size of the trial suggests a link between vitamin D intake and heart attack risk.
Nevertheless,”conclusions that vitamin D supplementation does not alter risk of cardiovascular disease are premature”, the authors noted.
Further work is now warranted to determine whether this protective effect is indeed more marked in those who are already taking statins or other cardiovascular drugs.