Selenium enriched milk increases protective biomarkers

Australian researchers have found that supplementing dietary intake of selenium using selenium enriched milk or selenium yeast results in increased levels of proteins that may protect against colorectal cancer. The study, presented today at the Australian Gastrointestinal Week annual conference, found that regular supplements of selenium enriched milk or selenium yeast increase colonic selenoprotein P (SeP) mRNA levels in healthy volunteers. The selenium enriched milk, however, resulted in a more sustained up-regulation of SeP and GPx-2 mRNA in human colonic epithelium over a six week wash-out period. Both SeP and GPx-2 have been shown to be biomarkers for risk of colorectal cancer in mouse models. The selenium enriched milk, made by feeding selenium yeast to dairy cows, also doubled the rectal GPx-2 mRNA in the study participants, while the yeast supplements did not. All of the 23 participants in the study, who were randomised to receive selenium-enriched milk (150µg/day) or selenium yeast (150µg/day) for six weeks, showed significantly increased plasma selenium from below 100µg/L at baseline to between 120-140 µg/L at the end of the supplementation (p<0.01). Both supplements were well tolerated and showed no signs of toxicity. “When compared to yeast as a means of getting selenium into our bodies, the fortified milk provided a significant benefit in the bowel,” said Professor Graeme Young, one of the authors of the study. The authors recommended that human trials, using adenomas as an endpoint, should be undertaken....