Rosehips may provide an effective alternative treatment for sufferers of crippling rheumatoid arthritis, according to a new research by scientists in Germany and Denmark.
Severely affected patients already being treated with conventional drugs experienced significant improvement after taking capsules of rosehip powder for six months, a pilot study showed.
Experts now want to conduct more extensive trials, which could form the basis of new clinical guidelines.
Scientists said the rosehip remedy, called LitoZin, may in future help reduce spending by health-care services on expensive new rheumatoid arthritis drugs.
Rheumatoid arthritis (RA) is a painful and debilitating autoimmune disease, which affects millions of people worldwide.
It occurs when the immune system attacks the joints, causing swelling and damage to cartilage and bone.
Traditional treatments, such as the disease-modifying anti-rheumatic drug (DMARD) methotrexate, have only limited effectiveness.
Newer medicines, including TNF Alpha inhibitors and the latest "smart" drugs targeting different parts of the immune system, are now becoming available, but are so costly it is questionable how many patients will receive them.
Treating just one patient with anti-TNF drugs, which act on a particular signalling molecule, costs up to $25,000 a year.
LitoZin, made from processed ground rosehips, is already widely used by patients with osteo-arthritis, a less serious condition caused by general wear and tear of the joints.
One month's supply of the supplement retails over-the-counter for less than $30.
The new research was prompted by RA sufferers who claimed they had also been helped by the product.
Scientists who conducted the trial in Copenhagen and Berlin said they were surprised by the results, since RA is a far more serious and challenging disease than osteo-arthritis.
A total of 89, mostly female patients with an average age of 57 were recruited, all seriously affected by RA which they had suffered for more than 18 years. Of these, 74 stayed in the trial for the full six months.
Thirty-three were randomly assigned to a group taking LitoZin on top of their regular medication. The remaining 41 were given a "dummy" capsule containing no active ingredients.
The patients were asked to fill in standard questionnaires used to assess pain, and the ability to carry out everyday tasks such as dressing, washing, opening doors, and cutting meat.
After six months, activity levels improved by 20 to 25 percent for those taking LitoZin. The number of joints causing them pain and discomfort fell by 40 percent, but did not change for patients treated conventionally without the rose-hip supplement.
Generally, the overall tenderness of painful joints was significantly reduced in patients given the supplement, and quality of life greatly improved.
Stefan Willich, from the Charite University Medical Centre in Berlin, who co-led the study, said: "I think we were all surprised to see such meaningful results. Rheumatoid arthritis is one of the most difficult medical conditions I'm aware of. It's a tough disease, which makes it all the more remarkable to find such beneficial effects from this natural remedy.
"We would like to see larger long-term trials, perhaps of several hundred patients. If these studies confirm what we have found, then I think we could be talking about clinical guidelines."