Dietary supplements encompass a wide variety of products from vitamins, minerals, and
botanicals to probiotics, protein powders, and fish oils. 1 During the past 2 decades, a
steady stream of high-quality studies evaluating dietary supplements has yielded
predominantly disappointing results about potential health benefits, whereas evidence of
harm has continued to accumulate. How consumers have responded to these scientific
developments is not known. In this issue of JAMA, 2 the report by Kantor and colleagues …