Results from a Korean study comparing users and non-users of complementary and alternative medicine. Not even a placebo effect shows up. Quote:
Compared with nonusers in subgroup analysis, users of alternative medical treatments, prayer, vitamin supplements, mushrooms, or rice and cereal reported clinically significant worse changes in some HRQOL [Health-Related Quality of Life] subscales. Conclusion: While CAM did not provide any definite survival benefit, CAM users reported clinically significant worse HRQOLs.