Vitamin C Linked to Increased Kidney Stones in Men
A new study showed that men who took high-dose vitamin C supplements doubled their risk of developing painful kidney stones.
The study, which is published in the scientific periodical JAMA Internal Medicine, did not however observe an increased risk between kidney stones and multivitamins - which contain lower concentrations of vitamin C.
During more than a decade of follow-up, the fully adjusted relative risk for kidney stones among men using vitamin C supplements was 1.92 (95% CI 1.33 to 2.77), according to Agneta Åkesson, PhD, and colleagues from the Karolinska Institute in Stockholm.
However, there was no risk associated with taking multivitamins (RR 0.86, 95% CI 0.62 to 1.19), Åkesson and colleagues reported online.
"As with all research, the results should be corroborated by other studies for us to be really sure," says study leader Agneta Åkesson, Associate Professor at Karolinska Institutet's Institute of Environmental Medicine. "Nor can we say anything about whether women run the same risk as men. But given that there are no well-documented benefits of taking high doses of vitamin C in the form of dietary supplements, the wisest thing might be not to take them at all, especially if you have suffered kidney stones previously."
The results of the study indicate that men who take vitamin C supplements (typically 1000 mg per tablet) are twice as likely to develop kidney stones as men who do not take any dietary supplements. The risk was also found to increase with the frequency of vitamin C supplement use. The regular use of multivitamins was not found to be associated with the risk of kidney stones.