Low blood levels of selenium are a risk factor for the progression of Barrett’s esophagus, a precancerous condition, according to a study.

Researchers found that patients with Barrett’s esophagus who had low selenium levels were at a two- to three-fold greater risk of developing advanced precancerous changes than patients whose selenium levels were in the middle or high end of the normal range.

The U.S. recommended dietary allowance for selenium is 55 micrograms (mcg) for adults. Fish, meat, bread, Brazil nuts and walnuts are good sources of dietary selenium.

Researchers do not recommend selenium supplements for people with Barrett’s esophagus at this time, and they caution that selenium supplements should only be taken in low doses. According to previous studies, high doses of selenium can be toxic, resulting in symptoms such as hair and nail loss, gastrointestinal problems and nerve damage, and could even promote cancer.

In the study, researchers analyzed data from 399 people with Barrett's esophagus and found that those with higher concentrations of selenium in their blood were less likely to have as many biological markers of progression toward cancer as compared to those with less selenium.

Researchers suggested that the nutrient might be most beneficial for people with later-stage disease, as selenium seemed to have the greatest effect on markers associated with advanced progression of Barrett's.

More research is needed to confirm the findings, researchers noted. The current study was limited because data was only collected at a single point, rather than following the same people over time.

Other research has shown that taking non-steroidal anti-inflammatory drugs such as aspirin and keeping weight at a healthy level may also inhibit the progression of Barrett’s.

Barrett’s esophagus progresses into esophagus cancer in only five percent to 10 percent of patients, however, more than 90 percent of patients with invasive esophageal cancer die within five years of diagnosis.

Further, Barrett's-related esophageal cancer strikes more than 8,000 Americans a year, and the incidence is rising faster than that of any other cancer in the United States, for unknown reasons.

Since the cancer is rapidly fatal, it’s important to find ways to prevent it, researchers said.

The findings suggest that adequate selenium consumption may inhibit the progression of Barrett’s esophagus. However, there is currently no proven, recommended therapy for reducing cancer risk among people with Barrett’s esophagus.

Eurekalert.org May 19, 2003