Study Rates Arthritis Supplements
Based on available evidence, some can help – but many don’t.
A new British report has found that few popular supplements have strong scientific evidence showing that they work for rheumatoid arthritis (RA), osteoarthritis (OA) or fibromyalgia. But some did rank as effective, including capsaicin, SAMe and Indian frankincense for OA, and fish oil for RA.
The lack of research data on complementary medicines “makes it very difficult for us to know whether they are effective, but equally we can’t be sure they are not effective,” says lead study author Gary J. Macfarlane, MD, PhD, professor and chair of epidemiology in the School of Medicine and Dentistry at the University of Aberdeen, in Scotland
The evidenced-based report is the second edition, updated with the latest clinical data, by Arthritis Research UK, a large medical-research organization. It was done to provide comprehensive information on the effectiveness and safety of supplements in an effort to help patients and clinicians make informed decisions.
“What this report is not about is telling arthritis patients whether to use a complementary therapy or not,” says Dr. Macfarlane. “Each individual must make that decision for themselves, and it is likely to be partly based upon how effective these therapies are, their safety and their cost.”
Researchers evaluated 31 complementary medicines taken either by mouth or applied to the skin that were found to have quality studies available. Each was scored for effectiveness based on users’ improvements in pain, disability or quality of life, with “1” suggesting the supplement is not effective and “5” suggesting consistent evidence of efficacy. Few supplements were given a “5” rating.
For OA, capsaicin, a topical treatment extracted from chili peppers, scored 5. Two supplements scored 4 – SAMe, a compound found naturally in the body, and Indian frankincense, a plant extract that blocks the production of hormone-like substances thought to trigger joint inflammation.
For RA, nearly three-quarters of the supplements evaluated scored poorly, but fish oil scored 5.
For fibromyalgia, no supplement scored 5 or 4.
Glucosamine, which is very popular in the United States, showed little evidence to support reduction of pain or positive joint changes; glucosamine hydrochloride scored 1 and glucosamine sulfate was given a 2.
“I think we were surprised that in many cases there was so little evidence for effectiveness for therapies which were commonly used,” says Dr. Macfarlane. “There was a lack of evidence for [the use of] collagen, homeopathy, vitamin supplements and willow bark” for RA and OA, he adds.
Despite the shortage of supporting evidence, many people believe supplements are effective, says pharmacist Donald Miller, professor and chair of pharmacy practice at North Dakota State University in Fargo.
In fact, half of adult Americans use supplements, including multivitamins, minerals and herbs, according to the Centers for Disease Control and Prevention (CDC). And according to Consumer Reports, U.S. consumer spending in the steadily growing industry accounted for almost $27 billion in 2009.
People with arthritis and musculoskeletal conditions often try alternative medicines in an effort to manage their pain, the researchers say.
Miller agrees. “There’s this feeling that there’s got to be a magic bullet, that there’s something better out there,” he says. “It’s difficult to live with pain all the time.”
Researchers also issued safety scores for the compounds, using a traffic-light system. Those that scored “green” were found to have only minor and infrequent side effects, an “amber” rating was issued to compounds having commonly reported and in some cases more serious side effects, and those that received a “red” rating have serious side effects. None of the supplements evaluated were issued a “red,” or unsafe, rating. But six supplements were given an “amber” rating, including flaxseed oil (for RA).
“If people are taking [supplements] with no side effects, they can continue,” Miller says, given the report’s safety findings. “But if they are considering taking them, they should think carefully about it, and talk to their doctor or pharmacist about better established alternatives.”
The U.S. Food and Drug Administration does not regulate supplements as it does drugs. Therefore, makers of these alternative products do not need to prove safety or efficacy, leaving the buyer to make decisions on his or her own.