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Vitamin C can cause nephrolithiasis
Last reviewed: 16.10.2021
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Scientists from the University of Carolina (Sweden) announced the relationship between the use of food supplements with vitamin C and the formation of kidney stones. In the cold season, most adults take vitamin complexes to improve immunity and prevent colds, but until now no one has suspected that regular consumption of too much vitamin C can 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 used by the patient. Doctors do not insist that ascorbic acid itself is capable of forming a foreign body in the kidneys, but consider it necessary to warn those who have ever had problems with the genitourinary system from excessive intake of vitamin C.
The study lasted more than 11 years and consisted in the observation of a large number of middle-aged and elderly men. The doctors followed the analysis of the volunteers, who also answered a number of questions related to their well-being and way of life. The total number of participants in the experiment was about 23,000 people, of which only 900 people regularly consumed food supplements with vitamin C. A careful analysis of the data allowed to determine 460 cases of stone formation in the kidneys. Physicians managed to find out that the highest risks of nephrolithiasis are present in middle-aged and elderly men who have a habit of using vitamin C in the form of additional supplements. The acceptable dosage of vitamin C is 100 mg / day, with increasing dosage the chance of kidney stones formation is doubled.
If we compare the data obtained during the study, we see that among people who abused vitamin C, 4% had urolithiasis. Among those who do not resort to additional sources of ascorbic acid, patients with nephrolithiasis only 1.4%. Physicians at the University of Carolina 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 the kidneys. Kidney stones are formed from chemical compounds that form small crystals. In some cases, stones can be excreted independently along with urine, in more complex cases, the surgeon's intervention is necessary.
Scientists do not recommend to completely abandon the use of vitamin supplements, but advise to pay attention to multivitamin complexes, in which the dosage of vitamin C is not too high. Specialists noted that urolithiasis due to excessive intake of vitamin C is less of a concern for female representatives and those who have never had problems with the genitourinary system. In any case, the daily norm of ascorbic acid is not more than 100 mg. If you do not have the opportunity to receive vitamin C from natural products, you should pay attention to multivitamin complexes.