Feb. 6 (UPI) -- A study from Queen's University Belfast has found that common herbal supplements may be doing more harm than good.
Researchers found that over-the-counter herbal supplements used to treat obesity and erectile dysfunction are labeled fully herbal but may include dangerous pharmaceutical ingredients not listed on the label.
A research team from Queen's University Belfast, Kingston University London and LGC, an international life sciences testing company, found that many supplements for weight loss contain Sibutramine.
Sibutramine, also known as Reductil, is no longer used throughout the United States and Europe because it was linked to an increased risk of heart attack and stroke.
"Our review looked at research from right across the globe and questioned the purity of herbal food supplements," Emeritus Professor Duncan Burns, an analytical chemist from Queen's University Belfast's Institute for Global Food Security and author of the study, said in a press release. "We have found that these supplements are often not what customers think they are -- they are being deceived into thinking they are getting health benefits from a natural product when actually they are taking a hidden drug."
Researchers found that supplements for erectile dysfunction contained tadalfil and sulfoaildenafil, which contain nitrates and can drastically lower blood pressure and cause serious health problems.
"These products are unlicensed medicines and many people are consuming large quantities without knowing the interactions with other supplements or medicines they may be taking," Burns said. "This is very dangerous and there can be severe side effects. People who take these products will not be aware they have taken these substances and so when they visit their doctor they may not declare this and it can be difficult to determine what is causing the side effects. It is a very dangerous situation."
The study was published in the Journal of the Association of Public Analysts.