Men who take vitamin C supplements are at higher-than-average risk of developing kidney stones, a new study from Sweden suggests.
The analysis included 907 men who said they took regular vitamin C tablets and more than 22,000 who didn't use any nutritional supplements.
Of the vitamin C users, about one in 30 developed kidney stones for the first time during the study a rate almost double that of the group not on the vitamin. Men who took vitamin C supplements at least once a day had the highest risk of kidney stones, researchers reported yesterday in JAMA Internal Medicine.
In a comment accompanying the study, Robert H. Fletcher, MD, of Harvard Medical School, traced the history of vitamin C and disease from 1753, when British medical officer James Lind published a report of sailors with scurvy improving when given limes (because of which, British sailors are called limeys by some).
Enthusiasm for vitamin C rose in the 1970s, when two-time Nobel Prize winner Linus Pauling advocated its use for prevention of the common cold, as well as for protection against cardiovascular disease and cancer. "Unqualified support from a famous scientist perpetuates belief in an idea up to a point, but in the longer run evidence wins out," Fletcher wrote.
Furthermore, ACSH friend Dr. David Seres, director of medical nutrition at Columbia University Medical Center, adds that sudden cessation of high doses of vitamin C can induce scurvy, even if subsequent levels and intake are normal. Between this, the kidney stone problem and the absence of evidence that megadoses of vitamin C are useful in any way, it is clear that this should be avoided.
Randomized trials since then have shown that vitamin C supplementation has failed to prevent or cure any disease (except vitamin C deficiency), and the current analysis confirmed the findings of another cohort study, that high doses can contribute to men's likelihood of developing kidney stones.
ACSH s Dr. Ruth Kava adds, Linus Pauling really set the stage for all types of megavitamin therapy with his unsubstantiated support for high dose vitamin C consumption. But this has not been shown to work, and as in this report, may be linked to adverse health outcomes.
ACSH s Dr. Josh Bloom says, If you ve never had a kidney stone, you don t have the slightest idea of the definition of the term pain. Because if people really knew, bottles of vitamin C would be flying out of apartment windows at such a rate that it would resemble the ticker tape parade the last time the Yankees won the World Series.