the trial that make puzzled researchers.
in 1994 trial daily megadoses of the antioxidant beta-carotene increased the risk of lung cancer in male smokers by 18 percent.
in 1996 trial was stopped early after researchers discovered that high-dose beta-carotene and retinol, another form of vitamin a, increased lung cancer risk by 28 percent in smokers and workers exposed to asbestos.
in 2011 trail involving more than 35,500 men over 50 found that large doses of vitamin e increased the risk of prostate cancer by 17 percent.