“A higher intake of vitamin E can cut the risk of lung cancer by more than half, researchers from the University of Texas M.D. Anderson Cancer Center has found.
In a new study published in the International Journal of Cancer, researchers used the National Cancer Institute’s Health Habits and History Questionnaire and Food Frequency Questionnaire to assess the dietary intakes of 1,088 lung cancer patients and 1,414 healthy participants. Participants were further surveyed about various lifestyle factors, including smoking.
The average age of the healthy participants was 60.8, while the average age of the lung cancer participants was 61.7.
Vitamin E occurs in two main groups, the tocopherols and tocotrienols. Each of these groups, in turn, contains four varieties, named alpha, beta, gamma and delta. For the current study, the researchers analyzed participants’ dietary tocopherol intake, dividing it up based on which form it occurred in.
“To the best of our knowledge, this is the first study to compare dietary intakes of the different forms of tocopherols (alpha-, beta-, gamma and delta-tocopherol) and lung cancer risk,” the researchers wrote.
The researchers divided participants into groups based on intake of tocopherols in general and the four different varieties individually, then compared the rate of lung cancer between the groups.
Participants with the highest tocopherol intake were found to have a 55 percent lower risk of lung cancer than participants with the lowest intakes. The average intakes of the two groups were more than 12.95 milligrams per day and less than 6.68 milligrams per day, respectively.
A powerful protective correlation also showed up for alpha-tocopherol, with those consuming the most having a 53 percent lower risk of lung cancer than those with the lowest intake. The highest alpha-tocopherol intake averaged more than 7.73 milligrams per day, while the lowest averaged less than 4.13 milligrams per day.
Higher consumption of beta-, gamma- or delta-tocopherol alone, however, appeared to have no influence on cancer risk.
“We found consistent independent associations for increased dietary alpha-tocopherol intake and risk reduction but did not find independent associations for gamma-, beta- and delta-tocopherol in lung cancer risk,” the researchers wrote.
The European diet typically contains vitamin E in the form of alpha-tocopherol, while the U.S. diet tends to contain it in the form of gamma-tocopherol. Vitamin pills contain mostly alpha-tocopherol.
The study was not designed to analyze by what mechanism tocopherols in general or alpha-tocopherol in particular might act to reduce cancer risk.
“Our data should be useful in stimulating additional epidemiologic and basic science research in the relationship of different forms of vitamin E and cancer,” the researchers wrote.
Foods high in vitamin E include asparagus, avocado, green leafy vegetables, nuts, olives, seeds and wheat germ. A variety of vegetable oils, including canola, corn, cottonseed, red palm, sunflower and soybean are also high in the vitamin.
The new study is not the first to link vitamin E with cancer protection. The vitamin is well known to function as an antioxidant, meaning that it plays an important role in removing particles known as free radicals from the body. These electrically charged molecules are believed to be responsible for some of the cell damage that leads to cancer, other diseases, and the symptoms of aging.”