RUTGERS (US) — Two forms of vitamin E found in nuts and vegetable oils may protect against cancer, while the type most commonly used in supplements has no benefit, research shows.
Scientists at Rutgers and and the Cancer Institute of New Jersey believe that two forms of vitamin E—gamma and delta-tocopherols—found in nuts and in soybean, canola, and corn oils do prevent colon, lung, breast, and prostate cancers.
“There are studies suggesting that vitamin E actually increases the risk of cancer and decreases bone density,” says Chung S. Yang, director of the Center for Cancer Prevention Research at Rutgers.
“Our message is that the vitamin E form of gamma-tocopherols, the most abundant form of vitamin E in the American diet, and delta-tocopherols, also found in vegetable oils, are beneficial in preventing cancers while the form of vitamin E, alpha-tocopherol, the most commonly used in vitamin E supplements, has no such benefit.”
In a study reported in the journal Cancer Prevention Research, the researchers discuss animal studies conducted at Rutgers as well as human epidemiological studies that have examined the connection between vitamin E and cancer.
“When animals are exposed to cancer-causing substances, the group that was fed these tocopherols in their diet had fewer and smaller tumors,” Yang says. “When cancer cells were injected into mice these tocopherols also slowed down the development of tumors.”
In researching colon cancer, Yang pointed to another recently published paper in Cancer Prevention Research indicating that the delta-tocopherol form of vitamin E was more effective than other forms of vitamin E in suppressing the development of colon cancer in rats.
Recently, in one of the largest prostate cancer clinical trials in the United States and Canada, scientists found that the most commonly used form of vitamin E supplements, alpha-tocopherol, not only did not prevent prostate cancer, but its use significantly increased the risk of this disease among healthy men.
This is why, Yang says, it is important to distinguish between the different forms of vitamin E and conduct more research on their effects.
“For people who think that they need to take vitamin E supplements,” Yang says, “taking a mixture of vitamin E that resembles what is in our diet would be the most prudent supplement to take.”
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