Medical expert of the article
New publications
Vitamin C can cause kidney stone disease
Last reviewed: 01.07.2025

All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Scientists from Karolinska University (Sweden) have announced a link between the use of vitamin C supplements and the formation of kidney stones. During the cold season, most adults take vitamin complexes to boost their immunity and prevent colds, but until now no one suspected that regularly consuming too much vitamin C could be dangerous to health.
The results of a study conducted by Swedish scientists show that the risk of kidney stones increases depending on the amount of vitamin C consumed by the patient. Doctors do not insist that ascorbic acid itself is capable of forming a foreign body in the kidneys, but they consider it necessary to warn those who have ever had problems with the genitourinary system against excessive consumption of vitamin C.
The study lasted over 11 years and consisted of observing a large number of middle-aged and elderly men. Doctors monitored the volunteers' tests, who also answered a number of questions related to their health and lifestyle. The total number of participants in the experiment was about 23,000 people, of whom only 900 regularly took vitamin C supplements. A thorough analysis of the data allowed us to identify 460 cases of kidney stone formation. Doctors were able to find out that the highest risks of nephrolithiasis are present in middle-aged and elderly men who have a habit of taking vitamin C in the form of additional supplements. The acceptable dosage of vitamin C is 100 mg / day, with an increase in the dosage, the chance of kidney stones doubles.
If we compare the data obtained during the study, we will see that among people who abused vitamin C, 4% had urolithiasis. Among those who do not resort to additional sources of ascorbic acid, only 1.4% suffer from nephrolithiasis. Doctors from Karolinska University suggest that the reason for this relationship is that vitamin C is excreted from the body with urine in the form of oxalate, which is one of the main components of kidney stones. Kidney stones are formed from chemical compounds that form small crystals. In some cases, stones can be excreted on their own with urine; in more complex cases, surgical intervention is necessary.
Scientists do not recommend completely abandoning the use of vitamin supplements, but advise paying attention to multivitamin complexes, in which the dosage of vitamin C is not too high. Experts noted that urolithiasis due to excessive consumption of vitamin C is less likely to affect women and those who have never had problems with the genitourinary system. In any case, the daily norm of ascorbic acid is no more than 100 mg. If you are unable to get vitamin C from natural products, you should pay attention to multivitamin complexes.