A new study conducted by researchers from RCSI shows that higher selenium levels are associated with decreased risk of bowel cancer, especially in women. The HRB funded study is part of a collaborative European study and has been published in the International Journal of Cancer.

Selenium is a trace mineral micronutrient found in food like shellfish, salmon, Brazil nuts, meat, eggs, grains and onions. It is needed for many functions in the body, but particularly the effective functioning of the immune system and in controlling inflammatory responses linked to cancer development.

The association of selenium status with bowel cancer development is controversial because some studies have indicated that increasing selenium intake does not have any association with bowel cancer development.

“The key difference in our study is that by measuring the baseline level of selenium among the study participants, we found that many Western Europeans have insufficient selenium to allow optimal functioning of important proteins for cancer prevention. This is in contrast to North Americans, who generally have higher baseline levels of selenium which is likely to explain why studies there would show no significant correlation between increasing their selenium intake and reducing bowel cancer,” says lead researcher Dr David Hughes, from the RCSI, Department of Physiology & Medical Physics.

The different results of this study to those from previous studies carried out in the United States may be due to the difference in baseline selenium levels of study participants. This study was conducted across 10 European countries and the research suggests that where selenium is sub-optimal, increasing selenium may help reduce or prevent bowel cancer cancer, especially in women.

“Our study indicates that there is a strong case to do a trial, where we provide a supplement to people who have low levels of selenium, to see if this would help reduce or prevent bowel cancer in populations with sub-optimal selenium levels.”

The study was carried out in conjunction with Emory University, Atlanta; International Agency for Research on Cancer, France; Institute for Cell and Molecular Biosciences, Human Nutrition Research Centre, Newcastle University, UK and collaborators in the European Prospective Investigation of Cancer and Nutrition Cohort (EPIC) study.