EpiCor's discovery as an immune-system supplement was quite accidental, and the yeast-based product has passed several human trials with no apparent side effects. EpiCor users have reported decreased incidence of colds and other illnesses. Embria Health Sciences, maker of EpiCor, stresses that the supplement works to balance immune systems and doesn't fight colds or flu, so it's more of a preventive measure.
EpiCor's beginnings go back to the Diamond V Mills company in Iowa, which for decades has made a special yeast culture animal-feed additive that helped increase production in dairy cows. Over time, an insurance company noted that certain employees — the ones exposed to the yeast product — rarely reported illnesses. The company tested its fermented yeast in the lab and found the product had more antioxidants than blueberries.
EpiCor was tested with success in two separate studies with rats, who were given the equivalent doses of 210 daily capsules for 1.5 years. The rodents showed no toxic effects in either test. The supplement also was used without adverse effects in several human trials, and it was given a Generally Regarded as Safe, or GRAS, status by a panel of toxicologists.
EpiCor comes from brewer's yeast that has been processed. Regular brewer's yeast, however, is not to be taken with antidepressants, and it should not be taken with antifungal medicine. To be safe, discuss use of EpiCor with your doctor before beginning a regimen.