Adequate Selenium in Diet May Reduce Esophageal, Stomach Cancers

People who consume enough selenium from their diets are at a lower risk of developing cancers of the esophagus and possibly the stomach, say researchers at the Maastricht University Medical Center in The Netherlands. Most people get enough of the trace element through diet alone, and the selenium content of foods is largely determined by the selenium level of the soil in which they’re grown.

Jessie Steevens and colleagues calculated the frequency of several types of cancers – gastric cardia adenocarcinoma (GCA), esophageal squamous cell carcinoma (ESCC), and esophageal adenocarcinoma (EAC) – as a function of how much selenium the study’s 120,000 participants were taking in. Participants, all between the ages of 55 and 69, were initially asked for nail clippings to measure their selenium levels, and were followed for an average of 16 years.

The researchers say that EAC and GCA are of particular interest largely because the rates of these types of cancers have grown in the United States and Europe over the last few decades.

The team found that those with the highest selenium levels had a much reduced risk for developing ESCC, and a slightly lower risk for developing GCA – but the authors say this relationship was only “borderline significant.” For EAC, a correlation between selenium intake and reduced cancer risk was only present when the researchers specifically looked at women and non−smokers (i.e., the relationship did not exist for the cohort as a whole).

Taking in too much selenium is dangerous, so large doses of selenium supplements are not recommended.

The researchers say that EAC and GCA are of particular interest largely because the rates of these types of cancers have grown in the United States and Europe over the last few decades. The team does caution that more research will be needed in order to understand the relationship selenium and various cancers more fully.