Benefits of Vitamin C for gout patients lowered - study

Findings showed a modest vitamin C dose for eight weeks did not lower urate levels to a clinically significant degree in gout patients. Photo / Thinkstock

Vitamin C does not significantly lower uric acid levels in gout patients despite earlier studies touting its benefit, new research shows.

Researchers at the University of Otago have found that vitamin C may not be as beneficial to gout patients as previously thought.

Professor Lisa Stamp and her colleagues found that while supplementing the vitamin appeared to have a weak effect on lowering uric acid levels in some gout patients, it did not reduce those levels to a clinically significant degree in patients with established gout.

"While current treatments are successful in reducing the amount of uric acid in the blood, there are many patients who fail to reach appropriate urate levels and need additional therapies," Professor Stamp said.

"Vitamin supplementation is one such alternative therapy and the focus of our current study, which looked at the effects of vitamin C on urate levels in patients with gout."

The research is published in the latest edition of the American College of Rheumatology journal, Arthritis and Rheumatism.

Gout is an inflammatory arthritis that causes excruciating pain and swelling triggered by the crystallization of uric acid within the joints.

Medical evidence reports that long-term gout management requires treatment with medications that lower urate levels by inhibiting uric acid production or increasing uric acid excretion through the kidneys.

Professor Stamp's team recruited 40 gout patients and analysed their daily dosage of vitamin C as a supplement to other medication.

Findings showed a modest vitamin C dose for eight weeks did not lower urate levels to a clinically significant degree in gout patients.

The results differ from previous research which found that vitamin C reduced urate levels in healthy individuals without gout but with high levels of uric acid.

In fact, the new study found reduction of uric acid was significantly less in gout patients taking vitamin C compared to those who started or increased their dose of gout medication.

"Though vitamin C may reduce risk of developing gout, our data does not support using vitamin C as a therapy to lower uric acid levels in patients with established gout. Further investigation of the urate lowering effects of a larger vitamin C dose in those with gout is warranted," Professor Stamp said.