No heart disease benefits from taking multivitamins
Taking a daily multivitamin won’t make any difference to your risk of heart problems, according to the results of a large good-quality trial in older men.
BMJ Group News
What do we know already?
Lots of people take multivitamins, pills, or other remedies that seem to provide a convenient way to get most of the daily recommended amounts of the vitamins the body needs to stay healthy.
Some studies have followed people over time to see if there is a link between taking multivitamins and being less likely to have health problems, such as heart attacks and strokes, or to die from these kinds of heart problems. But these studies haven’t always been good quality and have yielded conflicting results.
This study, researchers say, is the first good-quality study to look at the link between taking multivitamins and preventing heart disease. This study looked at a group of 16,461 men in the US who, as part of an ongoing study of the long-term effects of taking multivitamins, were randomly split into two groups. One group took a multivitamin every day, and the other group took a dummy pill. After an average of 11 years, the researchers recorded how many men had heart attacks or strokes, or died of either a heart attack or a stroke. The researchers then compared whether there was any difference between the two groups.
What does the new study say?
Men taking a multivitamin did not have fewer heart attacks or strokes, compared with men who took a dummy pill.
Overall 1,732 men had heart problems, including 652 men who had heart attacks who hadn’t had one before, 643 men who had a stroke and 829 men who died of heart problems.
In both the multivitamin group and the dummy pill group, 11 in every 1,000 men had heart problems during the study.
Taking a multivitamin made no difference to the number of men in each group who had a heart attack or a stroke. In each case, 4 in 1,000 men had either a heart attack or a stroke, whether they took a multivitamin or not.
There was no difference between groups when the researchers looked at the number of men in each group who had heart failure, died of heart problems, or died for any reason. Looking separately at men who either did or didn’t have heart problems at the beginning of the study didn’t change the strength of the link.
Fewer men in the multivitamin group died of a heart attack, but in each group this benefit applied to around one man in every 1,000 and the researchers noted that this difference was only just large enough to rule out being due to chance.
How reliable is the research?
This study is a large, well-designed and good-quality trial that is likely to be reliable.
But the researchers say that their results may not apply to everyone. The men in the study were mostly white and had an average age of 64. We don’t know if the effects would have been any different in women, or people of a different age or ethnic background. There wasn’t any reason to think men in the study were under-nourished, and so it may be that they were fewer health gains to be had from taking a multivitamin, but we don’t know if this is true for everyone. A different combination of vitamins, or taking them at different doses, might have had a different effect on the results.