Daily multivitamin pill intake may not actually lower risk of death and help healthy adults live longer, a new study suggests.
Researchers from the US National Cancer Institute assessed data from nearly 400,000 healthy adults followed for more than 20 years.
The study found no association between a regular multivitamin use and lower risk of death.
Many adults regularly take multivitamins hoping the habit would improve their health, however, the exact benefits and harms of taking them daily remain unclear, the study, published on Wednesday in the journal Jama Network Open, said.
Some reports suggested a third of all US adults take multivitamins hoping it would prevent any potential disease in the future.
Existing research probing the link between their intake and mortality are limited by short follow-up times.
To over come this, the new study analysed data from three large, geographically diverse studies involving over 390,000 US adults who were followed for over two decades.
The study participants were generally healthy, with no history of cancer or other chronic diseases, researchers said.
With such a large data sample, the new research could mitigate the effects of likely biases that may have influenced previous studies.
For instance, in the previous studies, sicker participants may have already been more likely to increase their use of multivitamins.
And people with healthier lifestyles in general may have been assessed in earlier research as multivitamin takers.
The new long-term analysis showed that people who took daily multivitamins did not have a clearly lowered risk of death from any cause compared to those who did not take the pills.
Researchers did not find any differences in mortality from cancer, heart disease, or cerebrovascular diseases among those who took multivitamins every day.
The analysis also accounted for other factors such as race and ethnicity, education, and diet quality.
“In this cohort study of 390 124 US adults without a history of major chronic diseases, we did not find evidence to support improved longevity among healthy adults who regularly take multivitamins,” researchers wrote.
“However, we cannot preclude the possibility that daily MV use may be associated with other health outcomes related to aging,” they added.
