Regularly taking high-dose vitamin C pills can double the risk of kidney
stones, say researchers.
By Stephen Adams, Medical Correspondent
12:58PM GMT 05 Feb 2013
They made their finding after looking at the incidence of kidney stones
over 11 years in 23,355 men.
Those who took vitamin C supplements - which typically contain 1,000
milligrammes per tablet - were at twice the risk of developing the stones
compared to men who took no vitamins.
Those who took the high-dose pills most regularly were at the highest risk.
But taking vitamin C as part of a multi-vitamin - which tend to contain
much lower doses of the vitamin - did not raise the risk, found the
researchers from the Karolinska Institute in Sweden.
Kidney stones are small crystals of waste matter that form and can block a
part of the organ or the urinary tract, causing intense pain. They affect 10
to 20 per cent of men and three to five per cent of women.