Think twice about taking supplements that contain high doses of vitamin C—they increase the risk of kidney stones. This was confirmed by a recent study in JAMA Internal Medicine, which found that among 49,000 Swedish men, those who took vitamin C (typically 1,000 milligrams a day) were twice as likely to develop kidney stones as those who didn’t take the supplement.
In any case, there’s no convincing evidence that vitamin C supplements are of any benefit.
Multivitamins, which typically contain about 60 milligrams of C, were not associated with increased risk of kidney stones. Foods and beverages containing vitamin C have never been linked to stones. In fact, lemon juice and orange juice may help prevent them.