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The relationship between iron intake and blood pressure (BP) status has not been well established. Only 1 cross-sectional study has suggested an inverse association of dietary total iron intake and nonheme iron intake with BP. We investigated the relationship between total, heme, and nonheme iron intakes, markers of iron status, 5.4-y changes in BP, and the incidence of hypertension. A total of 2895 participants included in the Supplémentation en Vitamines et Minéraux Antioxydants cohort were followed up for 5.4 y. At least 3 repeated 24-h dietary records were performed at baseline and 5.4 y later. Hemoglobin and serum ferritin concentrations were assessed at baseline. Low nonheme iron intake at baseline was associated with a greater increase in systolic BP (SBP) and pulse pressure over time after adjustment for multiple possible confounding factors (P-trend = 0.002 and 0.0005, respectively). Conversely, participants in the 3rd tertile of nonheme iron intake at baseline had a 37% lower risk of hypertension after 5.4 y of follow-up compared with those in the first tertile (P-trend = 0.04). Heme iron intake was not associated with BP changes or risk of hypertension. Meat intake was positively associated with an increase in SBP (P-trend = 0.04). However, that relation became nonsignificant after adjusting for dietary pattern scores. Baseline hemoglobin and ferritin concentrations were not associated with changes in BP or incidental hypertension. Our data support a possible role of low nonheme iron intake, independent of heme iron intake, in the development of hypertension. [ABSTRACT FROM AUTHOR]

BACKGROUND: Dietary fruits and vegetables may enhance iron status because of their high vitamin C content. The potential association between iron status and intakes of specific fruits and vegetables, according to sex and menopausal status, must be investigated. OBJECTIVE: The objective was to assess the relation between dietary fruits, vegetables, and juices (FVJ) according to their vitamin C and fiber contents and serum ferritin and hemoglobin concentrations. DESIGN: A total of 4358 subjects, aged 35-60 y, of the Supplementation with Antioxidant Vitamins and Minerals (SU.VI.MAX) cohort were selected. Subjects had completed at least six 24-h-dietary records over 2 y. The relation between serum ferritin and hemoglobin, measured at inclusion, and dietary FVJ according to their vitamin C and fiber contents was assessed by multiple regression analysis. RESULTS: In premenopausal women, serum ferritin was positively associated with intakes of fiber-poor FVJ (up to 10% higher serum ferritin in the third tertile compared with the first tertile). In the whole sample, hemoglobin was positively associated with fruits, vitamin C-rich FVJ, FVJ ascorbic acid, and fiber-poor FVJ categories (up to 1.5 g/L higher hemoglobin concentration). CONCLUSIONS: Intakes of fiber-poor FVJ were associated with higher serum ferritin concentrations in premenopausal women and with higher hemoglobin concentrations in the whole sample. Our results suggest that the fiber content of fruits and vegetables influences iron stores in premenopausal women but has no influence in groups in whom nonheme-iron absorption is limited because of high iron stores. Other mechanisms are likely to be involved in the case of hemoglobin. Copyright © 2008 American Society for Nutrition [ABSTRACT FROM AUTHOR]