Multivitamin and Multimineral Supplements Review
Initial Posting: 4/25/2020
Sections: Jump to a section by clicking on its name.
What did CL Find?
Twelve out of 27 (44.4%) of the multivitamin/multimineral supplements selected by ConsumerLab.com for testing failed
to get our approval. These are marked as "Not Approved
" in the results table
Some had lower
levels of nutrients than the label claimed, some had higher
amounts, and two took longer than permitted
to disintegrate ("break apart") in solution. All product deficiencies were confirmed in tests in a second independent laboratory (see What CL Found
Of particular concern is that several products provided more than or close to the Upper Tolerable Intake Levels (ULs), above which there is increasing risk of toxicity with regular use. For example, two gummy vitamins listing 400 mg of folic acid were each discovered to contained more than 200% of these amounts, i.e., over 800 mg of folic acid. Not only is this far above the daily requirement (240 mg of folic acid, or 400 mcg DFE), but it puts one close to exceeding the UL of 1,000 mcg of folic acid and potentially over it if consuming folic acid from other sources, like fortified breakfast cereals.
Our Top Picks:
Among products that were "Approved", including products tested through CL's voluntary Quality Certification Program
, Top Picks
were selected for the following 10 categories based on best product quality, appropriateness of dosage, formulation, and value:
COVID-19 and Multivitamins:
Each Top Pick
can help assure adequate intakes of vitamin D, vitamin C, and zinc, which are important for proper functioning of the immune system without risking excessive intakes that can cause negative effects. (See more information about supplements and COVID-19
, the disease caused by the coronavirus SARS-CoV-2.)
What to look for in a multivitamin?
When selecting a multi, the most important thing is to be sure it lists the right amount of each essential vitamin and mineral. Check your own requirements using our RDA table
or the detailed information for each nutrient
in the Review.
What They Are:
Multivitamins/multiminerals (or "multis") are the most popular supplements among the general population in America. There's no standard formula for multis, so ingredients will vary dramatically from one brand to another. It would be impossible to make a one-size-fits-all multi anyway because nutritional needs depend on age, gender, health status, and several other factors.
What They Do:
In 2014, the U.S. Preventive Services Task Force reported that there is inadequate evidence regarding a benefit or risk of harm with multivitamins in healthy adults without nutritional deficiencies (excluding women who are or may become pregnant) (USPSTF 2014, based on studies reviewed in Fortmann, Ann Int Med 2013).
There is some evidence that taking multivitamins is associated with a reduced incidence of some types of cancers in certain populations. For example, a major study of male physicians 50 years of age or older found an 8% lower incidence of cancers among those taking a relatively modest-dose daily multivitamin compared to men taking placebo -- although there was no reduction in the mortality rate during the study period of approximately 11 years (Gaziano, JAMA 2012). The greatest reductions in cancer were among men with a prior diagnosis of cancer (27% fewer new cancers) and men with no family history of cancer (14% fewer cancers). There was no significant reduction in prostate cancer -- the most common type of cancer in the study, however, there was a 12% reduction in all other cancers combined. The supplement used in the study was Centrum Silver, although the formula in the study dated from 1997 and contained 400 IU of vitamin D3 , 5,000 IU of vitamin A with 50% beta-carotene . In the opinion of ConsumerLab.com staff, the recent changes to the formula would seem unlikely to have negatively affected outcomes and the new formula may be beneficial.
This same study of Centrum Silver found no significant effect on the risk of cardiovascular disease, including no significant reductions in heart attack, stroke, or death from cardiovascular disease, among men taking the multivitamin versus placebo (Sesso, JAMA 2012). Researchers found that taking the multivitamin was not associated with any gastrointestinal side effects, fatigue, drowsiness, skin discoloration, or migraine, but there was a 7% increased risk of skin rashes. This study was among 18 multivitamin studies included in a broader analysis that concluded that multivitamin/multimineral supplementation "... does not improve cardiovascular outcomes in the general population." However, most of the studies included in the analysis did not characterize the multivitamins used, making it impossible to generalize this conclusion to all formulas nor to populations with specific conditions or deficiencies (Kim, Circulation 2018).
Additional analyses of the long-term study using Centrum Silver among male physicians found no benefits on cognition or verbal memory, although the researchers noted that the population studied may have been too well-nourished to benefit from a multivitamin (Grodstein, Ann Int Med 2013). A 9% decrease in the risk of cataract was found among those taking Centrum Silver in this study, compared to those taking placebo, although there was no decrease in the risk of developing visually significant age-related macular degeneration (AMD) (Christen, Am Acad Opthal 2013). However, among participants who were randomized to also take a separate, daily, high-dose vitamin C supplement (500 mg synthetic ascorbic acid -- about 6 times the RDA), there was no reduction in cataract risk, while the risk of cataract decreased by 18% among those taking Centrum Silver (which contains 60 mg of vitamin C) without the additional vitamin C supplement.
A study in adults who previously suffered heart attacks found that giving them high-dose vitamins and minerals did not result in a statistically significant reduction in further cardiovascular events compared to those receiving placebo (Lamas, Ann Int Med 2013). The supplement consisted of 28 vitamins and minerals given as 6 large caplets daily and was designed by complementary and alternative medicine practitioners. It included amounts of vitamins A, C, and E and most B vitamins at several times the Daily Value, and up to three times the Daily Value for folate, selenium, chromium, and molybdenum. Patients took the supplement regimen for one to five years (median was 31 months) and were followed for two to five years (median was 55 months). Many people dropped out of the study due to the complexity of the regimen, although there was no evidence of harm.
There is little evidence from clinical trials showing that a specific multi can reduce the risk of dying from cardiovascular disease, cancer, or any other cause (Park, Am J Epidem 2011). However, a U.S. study found that people who had used multivitamin/multimineral supplements for at least 3 years were 35% less likely to have died of cardiovascular disease over the following 20 or so years, compared to those who had not taken a multi. This positive finding was largely driven by results for women in the study, who were 44% less likely to have had a cardiovascular-related death. None of the subjects had cardiovascular disease at the start of the study and the results were adjusted to avoid potentially confounding variables including race, education, aspirin use and blood pressure. Interestingly, the apparent benefit did not occur for people who had used multivitamins which lacked minerals, nor among people who had taken multis for less than 3 years at the beginning of the study (Bailey, J Nutr 2015). In addition, a study of women aged 50 to 79 years with invasive breast cancer found that those who used multivitamins were 30% less likely to have died from the disease, compared to non-users, over an average period of 7 years (Wassertheil-Smoller, Breast Canc Res Treat 2013). Adjusting for factors such as age, race, and the use of other supplements did not substantially change this estimate. Unfortunately, the study did not evaluate the specific multivitamin formulas used, so it is impossible to say which formula, if any, was associated with the lowest mortality.