Selenium for Prevention: Eating Your Way to Better DNA Repair?

Extract

For researchers who study the cancer-inhibiting mechanisms of selenium, the scientific literature generally comes in two flavors. Selenium is seen as either a beneficial scavenger of DNA-damaging oxygen free radicals or as a potent inducer of apoptosis that eliminates damaged, potentially cancerous cells.

Now a third flavor could be on the menu. Scientists at Indiana University in Indianapolis reported recently in the Proceedings of the National Academy of Sciences that high levels of selenomethionine, the primary organic form of selenium, prompts cells in culture to initiate DNA repair, a key mechanism in preventing cancer. The group, led by Martin Smith, Ph.D., shows that the nutrient indirectly switches on a DNA repair subpathway controlled by the regulatory protein p53.

The finding raises the intriguing, but still scientifically murky, possibility that people with functional p53 could boost their capacity for DNA repair by simply increasing their dietary intake of selenomethionine by, for example, eating Brazil nuts, a plentiful source of the amino acid. The idea hinges in part on previous studies indicating that some people are naturally more proficient at DNA repair than others and that this inherent difference can be correlated with cancer risk.