A PROSPECTIVE-STUDY OF THE INTAKE OF VITAMIN-C AND VITAMIN-B6, AND THE RISK OF KIDNEY-STONES IN MEN

Purpose: The association between the intake of vitamins C and B6, and kidney stone formation was examined. Materials and Methods: We conduct ed a prospective study of the relationship between the intake of vitam ins C and B6 and the risk of symptomatic kidney stones in a cohort of 45,251 men 40 to 75 years old with no history of kidney calculi. Vitam in intake from foods and supplements was assessed using a semiquantita tive food frequency questionnaire completed in 1986. Results: During 6 years of followup 751 incident cases of kidney stones were documented . Neither vitamin C nor vitamin B6 intake was significantly associated with the risk of stone formation. For vitamin C the age-adjusted rela tive risk for men consuming 1,500 mg. daily or more compared to less t han 250 mg. daily was 0.78 (95% confidence interval 0.54 to 1.11). For vitamin B6 the age-adjusted relative risk for men consuming 40 mg. da ily or more compared to less than 3 mg. daily was 0.91 (95% confidence interval 0.64 to 1.31). After adjusting for other potential stone ris k factors the relative risks did not change significantly. Conclusions : 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.