(RxWiki News) Some dietary supplements have proven benefits, either in association with prescribed medicines or on their own as alternative therapies. Now, one supplement's usefulness for gout patients is being called into question.
Vitamin C—despite popular belief—may not ease joint pain associated with gout, a new study on a small group of voluntary participants in New Zealand has concluded.
But, as many research studies have found, humans do need vitamin C to remain healthy.
"Ask your pharmacist about gout treatments."
New Zealand-based rheumatologist Lisa Stamp, MBChB, of the University of Otago in Christchurch, was the study's lead author.
Her research cited, among other previous studies, one in which almost 200 healthy volunteers who took 500 milligrams of vitamin C daily, then submitted to tests measuring their serum urate levels, did experience a modest reduction in that serum.
When there is too much serum urate in the body, the serum creates uric acid, which crystallizes and settles in the joints, causing gout.
For the eight weeks of Stamp's study, a group of 20 gout patients who were taking allopurinol, a drug typically prescribed to treat gout, were randomly selected to either have their allopurinol dosage increased or to have 500 mg daily of vitamin C added to their treatment regimen, according to Stamp.
A second group of 20 gout patients who do not take allopurinol were randomly chosen to either start taking that drug or to only take 500 milligrams of vitamin C daily, she wrote.
Neither group of Stamp's volunteers who received vitamin C experienced a significant enough reduction in serum urate to positively affect their gout.
Gout is a form of arthritis that typically attacks older adults, and attacks men more often than women. Younger adults, however, also have been diagnosed with gout.
“Effective long-term management of gout requires sustained reduction of serum urate,” Stamp wrote. “...Urate lowering can be achieved by either inhibiting production of uric acid...or increasing excretion of uric acid via the kidneys [using certain drugs]."
"Despite these treatments many patients fail to achieve the target [serum urate level]. Thus, there is the need for additional urate lowering therapies.”
Stamp reported no financial gain or investments that could influence study design or outcomes. The Health Research Council of New Zealand helped to fund the study.
Accepted by Arthritis & Rheumatism in February 2013, the study is being prepared for publication in that journal.