Several herbal supplements have the potential to reduce the effectiveness of medication prescribed to patients with certain heart-related conditions, according to a research review [1] published in the Journal of the American College of Cardiology.
Researchers focused on 10 supplements that may pose a risk for people who are already taking medications for high blood pressure, high cholesterol, and other conditions stemming from heart problems.
The supplements that were reviewed in the new research review were Asian ginseng, astragalus, flaxseed oil, garlic, ginkgo, grapeseed, green tea, hawthorn, milk thistle, and soy. Supplement products do not need to be approved by the U.S. Food and Drug Administration before they’re sold. Moreover, the facilities in which they are made are not supervised as well as those of pharmaceutical companies.
Experts Advise Against Use of Supplements
As is the case with any over-the-counter vitamins or other supplements, you should consult with your doctor before taking them to make sure they are safe for you. This study about herbs is the latest research to shed doubt on the effectiveness of popular supplements and to alert consumers of their potential risks to those with underlying health issues.
In 2013, the U.S. Preventive Services Task Force [2] decided not to recommend the use of multivitamins and minerals to prevent cardiovascular disease or cancer for people without nutritional deficiencies. This recommendation from the independent group of doctors came after numerous studies failed to show health benefits of taking vitamin and mineral supplements.
“Compared with conventional medications, herbal medications do not require clinical studies before their marketing or formal approval from regulatory agencies, and for this reason their efficacy and safety are rarely proven.,” researchers said in the latest study.
Potentially Harmful Interaction with Meds
There is insufficient clinical data on the effects of these herbal supplements, the study found. There are “potential relevant side effects,” including an increased risk of a harmful interaction with other medications, researchers said.
“Natural does not mean safe,” says the lead study author, Graziano Onder, M.D., an associate professor of medicine at the Universita Cattolica del Sacro Cuore in Rome. Dr. Onder and his colleagues summarized the evidence for the study.
Particularly, green tea, garlic, ginkgo, ginseng, and hawthorn have the potential to reduce the efficacy of certain heart medications or increase their side effects. Dr. Onder says that people taking aspirin or blood thinners should be especially cautious. Supplements combined with those medications can increase the risk of internal bleeding.
In an article [3] published last year in the American Journal of Cardiovascular Drugs, Jonathan Fialkow, M.D., [4] medical director of the chest pain center, cardiac rehabilitation and stress lab at Miami Cardiac & Vascular Institute at Baptist Hospital [5], cautioned against the use of dietary supplements as a substitute for prescribed medication.
The focus of Dr. Fialkow’s study was omega-3 dietary supplements containing fish oils, which are heavily promoted for heart health or for their anti-inflammatory qualities. But there is no clinical data supporting these claims, Dr. Fialkow said.
“It is important to recognize that dietary supplements do not always contain what is specified on their label…” said Dr. Fialkow.