October 11, 2013
Many Health Supplements Contain Unlabeled Ingredients
Brett Smith for redOrbit.com – Your Universe Online
Dietary supplements promise all sorts of benefits, from improved joint health to cognitive improvements.
However, a new Canadian study in the journal BMC Medicine has found the many of these herbal products contain ingredients that are not listed on the label and could be dangerous to ingest.
In the study, researchers from the University of Guelph tested 44 herbal products sold by 12 companies. Just two of the companies were found to produce authentic products without substitutions, contaminants or fillers.
Almost 60 percent of the herbal products tested contained plant species not listed on the label. Researchers also found product substitutions in 32 percent of their samples and over 20 percent of the supplements included fillers such as soybeans and wheat that were not listed.
"Contamination and substitution in herbal products present considerable health risks for consumers," said study author Steven Newmaster, a biology professor and botanical director of the Guelph-based Biodiversity Institute of Ontario (BIO). "We found contamination in several products with plants that have known toxicity, side effects and/or negatively interact with other herbs, supplements and medications."
One product labeled as St. John's wort was found to contain a plant with laxative properties that can cause chronic diarrhea and liver damage. Several other supplements contained Parthenium hysterophorus, which can cause oral ulcers and nausea.
One ginkgo product was found to include Eastern black walnut, which could severely affect people with nut allergies. Other products contained other unlabelled fillers, such as wheat and soy, which could also be a concern for people with certain allergies.
"It's common practice in natural products to use fillers such as these, which are mixed with the active ingredients,” Newmaster said. “But a consumer has a right to see all of the plant species used in producing a natural product on the list of ingredients."
Newmaster said his team formulated methods using genetic testing technology to identify and authenticate elements in the products.
"There is a need to protect consumers from the economic and health risks associated with herbal product fraud,” Newmaster said. “Currently there are no standards for authentication of herbal products."
The new study comes as medicinal herbs comprise the fastest-growing sector of the North American alternative medicine market. Over 1,000 companies around the globe make medicinal plant supplements worth more than $60 billion a year. Approximately, 80 percent of people in developed countries use these products, including vitamins, minerals and herbal remedies.
"The industry suffers from unethical activities by some of the manufacturers,” Newmaster said.
Recently, federal health officials had to start an investigation over a growing number of non-viral hepatitis cases in Hawaii thought to be caused by a dietary supplement product labeled as OxyElite Pro, which is marketed as a weight-loss supplement.
Non-viral hepatitis is a liver-damaging condition that cannot be passed from person to person and can be caused by alcoholism or drug use, including the excessive use of over-the-counter products such as Tylenol. Two patients have received liver transplants to combat their condition.