Medical experts suggest that people should start avoiding multivitamins as it doesn’t even help in preventing chronic diseases.

"The message is simple: Most supplements do not prevent chronic disease or death, their use is not justified, and they should be avoided," four physicians and public health experts wrote in an editorial accompanying the studies.

Researchers from the University and Brigham and Women's Hospital in Boston led by Francine Grodstein, a professor of medicine at Harvard, found that multivitamins had no effect on cardiovascular health and cognitive function and worst, as written in the editorial accompanying the studies, contents of the supplement like vitamin E, beta-carotene, and possibly increased doses of vitamin A increased the risk of death in some other trials.

The first study attempted to determine if multivitamins can help improve the cognitive function of those taking it. The researchers recruited 5,947 male participants aged 65 years and older. Some participants were asked to take a multivitamin pill everyday -- Pfizer Inc. Centrum Silver – while some were given placebo.

They were given cognitive assessments before the start of the study and underwent three more during the 12-year study period. The researchers then compared the results of the assessments and saw no difference.

Meanwhile, the vitamin-industry groups criticized the editorial notes saying that a study conducted in 2012 involving 15,000 men showed that there was a reduction on cancer risk.

The second study led by Gervasio Lamas, a Columbia University cardiologist, recruited 1,708 patient aged 50 and up who had suffered a heart attack at least six weeks earlier. Some of participants were given a higher-dose of multivitamins and some were given placebo. The results were also disappointing as it didn’t help lessen the risk of suffering from another heart attack or stroke or the risk of dying.

Researchers of the last study told the Wall Street Journal that the result was fairly undermined by patients withdrawing from the trial or failing to take their vitamins or placebos.

Dr. Lamas and others clarified that some vitamins and minerals have been proven beneficial in targeted populations. Folic acid, for instance, is widely recommended to pregnant women to prevent birth defects of the brain or spine.

Multivitamins also have shown benefit in malnourished populations in Africa and Asia, public health experts said.

Both studies were published in the Annals of Internal Medicine.