Contrary to popular belief, vitamins and antioxidant supplements may not actually be effective in preventing cardiovascular diseases. Researchers of the Republic of Korea recently conducted a large meta-analysis of randomized control trials using data from public research databases to show there is no link between these supplements and reduced risk of major cardiac events.
The analysis included data from 2,240 articles of 50 randomized control trials with 294,478 participants found using the databases of PubMed, EMBASE, the Cochrane Library, Scopus, CINAHL, and ClinicalTrials.gov. The supplements studied included vitamin A, vitamin B6, vitamin B12, vitamin C, vitamin D, vitamin E, ß carotene, folic acid, and selenium. The range of time participants took supplements and study followup was six months to 12 years. Finally, there were 39 trials with vitamins only, and 22 trials with antioxidants only.
Major cardiac events studied were cardiovascular death, myocardial infarction (heart attack), angina, sudden cardiac death, stroke, and transient ischaemic attack.
Compiled data showed the use of vitamin and/or antioxidant supplements was not associated with reduced risks of major cardiovascular events. The risk of developing a cardiovascular (CV) disease relative to exposure of participants was 1.00 with 95% CI from 0.98 to 1.02. This meant there was no average increase or decrease in major cardiac event risk after taking these supplements. Data on each individual supplement vs. risk of CV event can be found in table 2, table 3, and table 4 of the source article.
Analysis was done using participants who were not deficient in the supplements studied. Perhaps further research meta-analysis from the deficient perspective will yield results more in favor of supplements.
This study shows that there is currently no reason to take antioxidant or vitamin supplements if one is trying to prevent cardiovascular disease and isn’t deficient. Government agencies may want to reevaluate the efficacy and safety of such supplements before allowing them to be marketed as colloquial cardiovascular necessities.
Seung-Kwon Myung, Woong Ju, Belong Cho, Seung-Won Oh, Sang Min Park, Bon-Kwon Koo, and Byung-Joo Park. Efficacy of vitamin and antioxidant supplements in prevention of cardiovascular disease: systematic review and meta-analysis of randomised controlled trials. British Medical Journal, 2013.