In the U.S. more than $20 billion was spent on dietary supplements in 2005. Over $7 billion was spent on plant-based herbal dietary supplements such as grape seed extract, St. John's wort, ginseng and biloba extract.
Researcher Dr. Susanne Mertens-Talcott of Texas A&M University is looking into how useful plant-based phytochemicals, including antioxidants and herbal supplements, can be in the promotion of health and prevention of chronic diseases.
"My overall goal is to find out more about the safety and efficacy of phytochemical dietary supplements," she said. Because these items are already popular with consumers, "we need to follow up with research. We know very little about (dose) recommendations and how safe (they are)."