Heme iron from diet as a risk factor for coronary heart disease in women with type 2 diabetes

OBJECTIVE - Diabetes-related metabolic abnormality may aggravate the adverse effects of iron overload on cardiovascular health. However, little is known about whether iron consumption affects coronary heart disease (CHD) risk in diabetes. RESEARCH DESIGN AND METHODS - We prospectively assessed the associations of long-term intakes of dietary iron and red meat with CHD risk among 6,161 women who reported a diagnosis of type 2 diabetes. RESULTS - During 54,455 person-years of follow-up from 1980 through 2000, we documented 550 incident cases of CHD. After adjustment for age and BMI, high intakes of both heme iron and red meat were associated with a significantly increased risk of fatal CHD (P for trend = 0.003 and 0.018), coronary revascularization (P for trend = 0.02 and 0.06), and total CHD (P for trend = 0.0009 and 0.007). Women with the highest intake of heme iron had 50% (6-94%) increased risk of total CHD compared with those with the lowest intake. Further adjustment for other lifestyle and dietary factors did not appreciably change the associations. The positive association between heme iron and red meat intakes and CHD was more evident among postmenopausal women compared with premenopausal women. CONCLUSIONS - Our data indicate that higher consumption of heme iron and red meat may increase CHD risk among women with type 2 diabetes.