Summary Conclusion: In November of 2015, it was alleged that a consecrated host (communion bread wafer) from Saint Francis Xavier Church in Kearns, Utah, appeared to be bleeding. A thorough investigation has concluded that the host did not bleed, but the change of appearance in the host was due to red bread mold. The consecrated host has been disposed of in a reverent manner, as is required.
In an expeditious but careful manner the committee enlisted the services of a competent and credible scientist to conduct controlled testing of the host. Great care was taken to ensure the reverent handling of the consecrated host throughout the scientific examination. Upon completion of the prescribed tests, the scientist, with the assistance of a blind observer, concluded that the observed change in the host could be satisfactorily and conclusively explained by natural causes, namely the growth of what is commonly known as “red bread mold,” or red bacteria, most likely Neurospora cressa or Serratia marcescens.
The Church presumes that most situations appearing to be extraordinary phenomena are actually the result of natural causes. This is why the Church sets the evidentiary bar for proving a miracle quite high. In such matters the Church undertakes a thorough and unprejudiced examination of events that may appear to be miraculous. If, after a thorough investigation, the specific phenomenon can be satisfactorily and conclusively explained in natural terms, then a directly supernatural cause is ruled out. The alleged “bleeding host” from Saint Francis Xavier Parish is explained as a natural phenomenon.