Hemochromatosis gene mutations, body iron stores, dietary iron, and risk of colorectal adenoma in women

Background: Some experimental evidence suggests that iron may play a role in colorectal carcinogenesis, but human data for this role have been confl icting, possibly because of prob-lems related to study design or measurement of iron exposure. We assessed dietary iron intake and genetic and biochemical markers of iron status in a prospective, nested case – control study of women enrolled in the Nurses ’ Health Study. Methods: Among 32 826 women who provided a blood specimen, we identifi ed 527 women with colorectal adenoma and 527 matched control subjects who underwent endoscopy but were not diagnosed with adenoma after blood collection. We as-sessed iron intake, mutations in the HFE gene that are associ-ated with hereditary hemochromatosis (i.e., H63D and C282Y), and plasma biochemical measures of total body iron, including transferrin saturation and the ratio of the concentrations o