A prospective study of the intake of vitamins C and B6, and the risk of kidney stones in men
Curhan GC, Willett WC, Rimm EB, Stampfer MJ
Published in The Journal of Urology
Methodology
Prospective cohort analysis within the Health Professionals Follow-up Study; semiquantitative food-frequency questionnaires with multivariate-adjusted relative risks for incident symptomatic kidney stones.
Key Findings
In 45,251 men followed for 6 years (751 incident stones), neither high total vitamin C intake (>=1500 mg/day vs <250 mg/day, RR 0.78) nor high vitamin B6 intake (>=40 mg/day, RR 0.91) was associated with increased kidney stone risk; if anything, intakes trended inversely.
Conclusions
No association was found between high vitamin C or vitamin B6 intake and stone formation risk in this 6-year cohort, contrasting with later analyses showing harm from supplemental vitamin C in men.
Limitations
Observational cohort in health professionals limits generalisability; intake measured by food-frequency questionnaire with misclassification risk; only 6 years of follow-up; later longer analyses of the same and other cohorts found supplemental vitamin C did raise stone risk in men, so this null result should not be read as reassurance for high-dose supplements.
Supplements Studied
These data do not support an association between a high daily intake of vitamin C or vitamin B6 and the risk of stone formation, even when consumed in large doses.
These data do not support an association between a high daily intake of vitamin C or vitamin B6 and the risk of stone formation, even when consumed in large doses.
Related Health Concerns
Study Details
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Disclosures
Funding
US National Institutes of Health
This information is for educational purposes only. Always consult a healthcare professional before starting any supplement regimen.