I heard that the stem of certain Opuntia is used to treat type II
diabetes, diarrhea, and stomach ache. However, usefulness of Opuntia in treating
diabetes is not at all resolved. Although some researchers have shown a blood glucose-lowering effect of O. streptacantha http://www.ncbi.nlm.nih.gov/pubmed/3276479, another study of three other species of Opuntia (O. lasiacantha, O. velutina, and O. macrocentra) showed no such effect. Yet another study, on O.