The form of vitamin E found in many plant seeds might halt the growth of prostate and lung cancer cells, according to a Purdue University study. A team led by Qing Jiang has found that gamma-tocopherol, which occurs naturally in walnuts, pecans, sesame seeds, and in corn and sesame oils, inhibits the proliferation of lab-cultured human prostate and lung cancer cells. Gamma-tocopherol is also found in “mixed” vitamin E supplements.

“This is the first time gamma-tocopherol has been shown to induce death in lab-grown human cancer cells while leaving healthy cells alone,” said Jiang. “This could be wonderful news for cancer patients if the effect can be reproduced in animal models. But because most nutritional supplements contain only alpha-tocopherol, a different form of vitamin E that alone does not have these anticancer properties, it may be better to supplement the diet with mixed forms of vitamin E. The study shows that the anticancer effect is enhanced when mixed forms are used.”

In 2000, another study by Jiang and colleagues found that gamma-tocopherol inhibits inflammation, which had already been implicated in cancer development. They theorized that it might retard the progress of cancer and cardiovascular disease, and to test their hypothesis they exposed cultures of cancerous prostate and lung cells to the vitamin. Normal prostate epithelial cells were used as a control group.

“We discovered that as we increased the quantity of gamma-tocopherol, the cancer cells grew more slowly,” Jiang said. “But the normal prostate cells were not affected and grew normally. This could indicate that the vitamin could be used to target lung and prostate cancer cells without the damaging side effects of chemotherapy.”

Purdue University, Dec 14, 2004