The controversy behind whether selenium can fight cancer in humans might come down depending on which form of selenium people take. Researchers say that not all forms of selenium are same, but there is one type of selenium supplement that may produce a possible cancer-preventing substance more efficiently than another form of selenium in human cancer cells. Their study appears in the ACS' journal Biochemistry.
Hugh Harris and colleagues note that although the Nutritional Prevention of Cancer clinical trial showed that selenium reduced the risk of cancer, a later study called the Selenium and Vitamin E Cancer Prevention Trial did not show a benefit. A major difference between the trials was the form of selenium that was used. To find out whether different types of selenium have different chemopreventive properties, the researchers studied how two forms SeMet and MeSeCys are processed in human lung cancer cells.
The researchers found that MeSeCys killed more lung cancer cells than SeMet did. Also, lung cancer cells treated with MeSeCys processed the selenium differently than than cells treated with SeMet. They say that these findings could explain why studies on the health benefits of selenium sometimes have conflicting results.