Some proponents of alternative medicine prescribe bromelain, a pineapple extract, for cancer prevention, but there is insufficient evidence for its efficacy, according to the U.S. National Library of Medicine. Early research in mice suggests that bromelain may lead to new treatments for inflammatory bowel disease, which can lead to colon cancer, as of 2008, explains the American Institute for Cancer Research.
Another 2008 study at Duke University found evidence that the enzyme can reduce the symptoms of inflammatory bowel diseases such as Crohn's disease and ulcerative colitis, reports the National Center for Complementary and Integrative Health. The researchers did not find the results conclusive, however, and cautioned for additional research.
Although some individuals recommend bromelain as an anti-inflammatory to ease exercise-related muscle soreness, the research does not support its effectiveness, explains the U.S. National Library of Medicine. Possible side effects of bromelain include diarrhea, stomach pain and intestinal discomfort. Some individuals can be allergic to the enzyme, and pregnant and breast-feeding women should also avoid taking bromelain, as there is insufficient research regarding its safety as of 2015. Patients with scheduled surgery should cease usage a minimum of two weeks prior to the surgery, as the enzyme might increase the patient’s susceptibility to excessive bleeding.