Do vitamin and mineral supplements prevent cardiovascular disease (CVD) or cancer? The short answer is no, according to a recommendation statement by the U.S. Preventive Services Task Force (USPSTF) published in the June 21 JAMA. Its conclusions, based on evidence from a systematic review of 84 randomized controlled trials and six cohort studies, update and confirm the 2014 USPSTF recommendations against the use of such supplements for primary prevention. The task force found little or no evidence of benefit and even potential harm from some supplements, specifically beta carotene and vitamin E.
The following supplements were examined: multivitamin preparations, and vitamins A, B3, B6, B12, C, D, and E; beta carotene; folic acid; and the minerals calcium, magnesium, selenium, and zinc. The task force concluded that most vitamin and mineral supplements don't provide clinically important protective effects for CVD, cancer, or for all-cause mortality in healthy adults who do not have nutritional deficiencies. One new finding was a slightly lower cancer risk for those taking multivitamins; however, that evidence came from only three trials of short duration. The overall harms of taking supplements were few, but the task force cautioned against use of beta carotene supplements, which were associated with an increased risk of all-cause mortality, CVD mortality, and lung cancer in adult smokers or those with occupational asbestos exposure.
The recommendations apply to community dwelling adults only, exclusive of children, the chronically ill, hospitalized patients, those with nutritional deficiencies, or women who are pregnant or planning a pregnancy. This review's findings were consistent with the 2014 review, and the USPSTF again concluded that the evidence is insufficient to recommend these supplements for the primary prevention of CVD or cancer. The task force specifically recommended against prescribing beta carotene or vitamin E for those purposes. Read the full USPSTF recommendation statement at https://jamanetwork.com/journals/jama/fullarticle/2793446.-Gail M. Pfeifer, MA, RN