A 20-year study of 400,000 U.S. adults found that regular multivitamin use did not reduce the risk of mortality, calling into question the effectiveness of multivitamins in improving longevity.
The findings are based on an NIH study that analyzed more than two decades of dietary information from 390,124 U.S. adults.
An extensive analysis of data from nearly 400,000 healthy U.S. adults followed for more than 20 years found no association between regular multivitamin consumption and a lower risk of death. The study, led by researchers au National Institutes of Health‘s National Cancer Institute, was published on June 26, 2024, in Opening of the JAMA network.
Many adults in the United States take multivitamins in hopes of improving their health. However, the benefits and harms of regular multivitamin use remain unclear. Previous studies of multivitamin use and mortality have had mixed results and have been limited by short follow-up duration.
To further explore the relationship between long-term regular use of multivitamins and overall mortality and deaths from heart disease and cancer, the researchers analyzed data from three large, geographically diverse prospective studies involving a total of 390,124 U.S. adults followed for more than 20 years. Participants included in this analysis were generally healthy, with no history of cancer or other chronic diseases.
Analysis and results
Because the study population was so large and included long-term follow-up and detailed information on demographic and lifestyle factors, the researchers were able to mitigate the effects of possible biases that could have influenced the results of other studies. For example, people who take multivitamins may have healthier lifestyles in general, and sicker patients may be more likely to increase their multivitamin intake.
The analysis showed that people who took daily multivitamins did not have a lower risk of death from all causes than people who did not take them. There was also no difference in mortality from cancer, heart disease or cerebrovascular disease. The results were adjusted for factors such as race and ethnicity, education and diet quality.
The researchers noted that it is important to evaluate multivitamin use and risk of death among different types of populations, such as those with documented nutritional deficiencies, as well as the potential impact of regular multivitamin use on other health problems associated with aging.
