A supplemental iron dose of 60 mg Fe results in an increase in hepcidin after 24 hours and in a decreased iron absorption from the consecutive dose (n = 16). Doses are given both at 8:00 am on consecutive days 2 and 3 and compared with day 1 (control day) (study 2). (A) Hepcidin profiles during the observation period: boxes indicate median and interquartile ranges, whiskers describe the range of the data (min to max); boxes with different subscript letter differ significantly (P < .05). (B) Fractional iron absorption measured on days 2 and 3 from the 60-mg Fe dose. D1, day 1.