Folk and herbal remedies for arthritis are often found, after scientific scrutiny, to have beneficial effects. A recent study seems to support the role of turmeric as a spice that could help alleviate the pain and inflammation of rheumatoid arthritis.

Turmeric is the spice that flavors and gives yellow color to curries and other foods. It has been used for centuries by practitioners of Ayurvedic medicine to treat inflammatory diseases. Turmeric extract containing the ingredient curcumin is marketed widely as a dietary supplement for the treatment and prevention of a variety of disorders, including arthritis.

Janet L. Funk, MD and Barbara N. Timmermann, PhD, researchers at the University of Arizona, Center for Phytomedicine Research, set up a series of experiments to determine whether (and how) turmeric works as an anti-arthritic. They began by preparing their own extracts from the root of the plant and compared them with commercially available products.

Dr. Funk and her colleagues then tested in animal models a whole extract of turmeric root, only the essential oils, and an oil-depleted extract containing the three major curcuminoids found in the plant root.

Of the three extracts, the one containing the major curcuminoids was most similar in chemical composition to commercially available turmeric dietary supplements. It also was the most effective, completely inhibiting the onset of rheumatoid arthritis.

Dr. Funk states that, "This was the first study that has examined turmeric with the researchers' own prepared, well-defined extracts… the study represents the first documentation of the chemical composition of a curcumin-containing extract tested in a living organism… for anti-arthritic efficacy. It also provides the first evidence of anti-arthritic efficacy of a complex turmeric extract that is analogous in composition to turmeric dietary supplements."

The significance, she explains, is that "translating the results of trials such as these to clinical use depends on accurate information about the chemical content and biological activity of the botanical supplements available for use. This work paves the way for the preclinical and clinical trials needed before turmeric supplements can be recommended for medicinal use in preventing or suppressing rheumatoid arthritis."

Dr. Funk and her colleagues add, "This study also provides the first in vivo documentation of a mechanism of action -- how curcumin-containing extracts protect against arthritis."

"We found that the curcuminoid extract inhibits a transcription factor called NF-KB from being activated in the joint. A transcription factor is a protein that controls when genes are switched on or off. Once the transcription factor NF-KB is activated, or turned on, it binds to genes and enhances production of inflammatory proteins, destructive to the joint.

The finding that curcuminoid extract inhibits activation of NF-KB suggests that turmeric dietary supplements share the same mechanism of action as anti-arthritic pharmaceuticals under development that target NF-KB. It also suggests that turmeric may have a use in other inflammatory disorders, such as asthma, multiple sclerosis and inflammatory bowel disease."

In addition to preventing joint inflammation, Dr. Funk's study shows that the curcuminoid extract blocked the pathway that affects bone resorption. Bone loss associated with osteoporosis in women typically begins before the onset of menopause. Bone loss is also a feature of rheumatoid arthritis.

(Funk JL, Frye JB, Oyarzo JN, Kuscuoglu N, Wilson J, McCaffrey G, Stafford G, Chen G, Lantz RC, Jolad SD, Solyom AM, Kiela PR, Timmerman BN. Efficacy and mechanism of action of turmeric supplements in the treatment of experimental arthritis. Arthritis Rheum. 2006: 54 (11): 3452-3464).

Note: This story has been adapted from a news release issued by University of Arizona Health Sciences Center.

Author's note: This study is interesting from at least three points of view. First, it confirms the effectiveness of an herbal supplement for adjunctive treatment of rheumatoid arthritis and provides information on a possible mode of action. Second, it gives credence to the use of turmeric in standard dietary supplement form for arthritis. Third, the bone loss inhibiting effect of turmeric is an important one given the magnitude of osteoporosis as a public health issue.

I, for one, am making reservations to my favorite Indian restaurant as soon as I can.