CRN and NPA defend multivitamin use following “no mortality benefit” study outcome

01 Jul 2024 --- Following the recent publication of the “Multivitamin Use and Mortality Risk in 3 Prospective US Cohorts” study in Jama Network Open journal, the CEO of the Natural Products Association (NPA) responded by stating that the findings disputed nine decades of effort on its part to discredit such information.

Additionally, the SVP and CEO of the Council for Responsible Nutrition (CRN) emphasized the critical role that multivitamins play in filling essential nutrient gaps, particularly among vulnerable populations, highlighting research underscoring its benefits.

“There is substantial evidence supporting the role of multivitamins in addressing nutritional needs, reducing the risk of specific diseases and health conditions and supporting overall health,” says Andrea Wong, Ph.D., SVP, science and regulatory affairs of CRN.

“Analyzing mortality rates in isolation fails to recognize the range of health benefits of multivitamin use identified in rigorous scientific studies, including the reduction of birth defects, reducing cancer risk, slowing cognitive decline and many others.”

The cohort study, featuring 390,124 healthy adults and 20 years of follow-up, found that “daily multivitamin use was not associated with a mortality benefit,” suggesting that it does not support longevity. In the US, one in three adults regularly takes multivitamins for disease prevention, mainly older adults, women, non-Hispanic White individuals and those with a college education.

The study’s objective was to estimate the association of multivitamin use with mortality risk, accounting for confounding by a healthy lifestyle and reverse causation — a phenomenon that describes the association of two variables differently than you would expect — where individuals in poor health initiate its use. 

Undoing decades of work
Daniel Fabricant, Ph.D., CEO of the NPA, responded to the findings by saying: “Nearly 80% of US citizens use dietary supplements as a way to support their health and wellness. There is no magic bullet for mortality; however, diet and exercise are bullet-proof for life-long health goals. Unfortunately, this study peddles more of the same information NPA has spent nearly 90 years fighting.” 

CRN research indicates that many US citizens fail to meet the recommended daily intake for several essential micronutrients. According to the National Health and Nutrition Examination Survey (NHANES), substantial percentages of the population fall short in their vitamins A, C, D, E, K, calcium, magnesium and potassium intake. 

The current study’s authors cited a data review on multivitamin supplementation and mortality by the US Preventive Services Task Force (USPSTF) in 2022, which found insufficient evidence for determining benefits or harms owing, in part, to limited follow-up time and external validity.The CRN and the NPA have responded to the recent outcome of a cohort story, which found no mortality benefits from multivitamin consumption.  

In the current study, confounding a healthy lifestyle was a major concern because multivitamin users often follow more nutritious diets, exercise more and smoke less, known as the healthy user effect. Another determining factor was the need for more clarity on the changes in multivitamin use over time. Patients with diagnosed diseases may increase their multivitamin intake because of perceived health benefits, known as the sick user effect.

The scientists ran age- and sex-adjusted models and further adjusted for race and ethnicity, education, marital status, BMI, cigarette smoking, daily alcohol intake, daily coffee intake, Healthy Eating Index-2015, family history of cancer and individual supplement use. 

Wong notes that contemporary headlines focusing on mortality rather than quality of life should not discourage consumers from their multivitamin regimens, especially when individuals are aware their diets do not provide the full range of nutrients they need.  

CRN cites the 2020-2025 Dietary Guidelines for Americans, reporting that most people do not consume enough nutrients such as vitamin D, calcium and potassium. The organization regards multivitamins as a practical solution to bridge nutrient gaps. CRN also cites the “Supplements to Savings: US Health Care Cost Savings from the Targeted Use of Dietary Supplements, 2022–2030” report, which specifies that chronic diseases are avoidable with preventive care.

“Multivitamins are a vital component of US citizens’ health regimens. The evidence supporting their benefits is robust, compelling and continues to grow,” says Steve Mister, president and CEO of CRN. 

Deriving theory from multiple variables
By pooling data from three large cohorts, the researchers could explore heterogeneity across crucial population subgroups, including understudied sociodemographic subgroups, identified as a research gap in the 2022 USPSTF review. In stratified analyses, they found no evidence of effect modification by race and ethnicity, education or diet quality.

The participants who participated in the National Institutes of Health–AARP Diet and Health Study (327,732 participants) had no history of cancer or other chronic diseases, 42,732 in the prostate, lung, colorectal and ovarian cancer screening trial and 19,660 in the Agricultural Health Study. 

Multivitamin use was not associated with lower all-cause mortality risk in the first or second halves of follow-up. The researchers state the study has some limitations because it’s an observational study and residual confounding by poorly measured or unmeasured confounders may bias risk estimates. 

CRN goes on to cite recent findings from the COcoa Supplement and Multivitamin Outcomes Study (COSMOS-MIND), which observed strong evidence for the cognitive benefits of multivitamins. The study demonstrated that daily supplementation significantly slowed age-related cognitive decline in older adults, effectively improving memory performance.

CRN data shows that multivitamin users report better overall health and states that multivitamins are particularly beneficial for populations with higher nutrient needs, including pregnant women, older adults and those with restrictive diets.

By Inga de Jong