Daily multivitamins do not protect against cardiovascular events, finds studyBMJ 2012; 345 doi: http://dx.doi.org/10.1136/bmj.e7599 (Published 09 November 2012) Cite this as: BMJ 2012;345:e7599
Taking a daily multivitamin does not protect against cardiovascular events or death from cardiovascular disease, a large 10 year study of middle aged doctors has found.
Researchers from Brigham and Women’s Hospital and Harvard Medical School analysed data on multivitamin use and cardiovascular events from the Physicians’ Health Study II, a large scale trial testing the effects of long term use of a common multivitamin on the risk of major cardiovascular events and cancer. A total of 14 641 male US doctors who were 50 years or over (mean age 64) at the start of the study in 1997 were included, including 754 men with a history of cardiovascular disease.
By June 2011 and a follow-up of 11.2 years 1732 men had had major cardiovascular events, including 652 first heart attack and 643 first strokes. A total of 829 men had died from cardiovascular disease, with some men experiencing multiple events, show results reported in JAMA.1
But the rate of cardiovascular events was the same among men who took a multivitamin every day (11 events per 1000 person years) as for those on placebo (10.8 per 1000 person years) (hazard ratio 1.01; 95% confidence interval, 0.91 to 1.10).
There was also no difference between the groups on total myocardial infarction (3.9 and 4.2 events per 1000 person years; hazard ratio 0.93, CI 0.800 to 1.09), total stroke (4.1 and 3.9 events per 1000 person years, HR1.06; CI 0.91 to 1.23), or cardiovascular mortality (5.0 and 5.1 events per 100 person years; HR 0.95, CI 0.83 to 1.09). And multivitamins did not affect total mortality (HR 0.94, CI 0.88 to 1.02). The results were the same for men who had underlying heart disease.
The US population spends billions of dollars on multivitamins every year, says the paper, and people who believe they are deriving protection from taking them may be less likely to make changes to their lifestyle.
Results from the cohort on the impact of multivitamins on cancer, eye disease, and cognitive decline are to be published at a later date.
Cite this as: BMJ 2012;345:e7599