The binding properties of raw vegetable fiber towards bivalent cations suggested the prescription of brain as a dietary supplement to limit intestinal calcium absorption in hypercalciuric patients. A group of 18 patients with a specific diagnosis of absorptive hypercalciuria received a dietary supplement of 14 gm. wheat bran at the 2 principal meals for 90 days. A complete assessment of mineral metabolism was performed after 45 and 90 days. Mean basal calciuria was 357 mg. per 24 hours and a significant decrease was noted after 45 days (245 mg. per 24 hours) and 90 days (240 mg. per 24 hours), with a p value of less than 0.01. Urinary oxalate did not vary significantly (0.34 to 0.38 to 0.31 mMol. per 24 hours) and neither did phosphate levels (1,020 to 900 to 893 mg. per 24 hours). A slight and pathologically insignificant decrease was noted in serum iron and urinary magnesium; this fact could be considered a side effect owing to the nonselective binding properties of fiber. Therefore, the positive results achieved confirm the effective action of wheat bran in the treatment of correctly diagnosed absorptive hypercalciuria.