Relationship between iron status and dietary fruit and vegetables based on their vitamin C and fiber content

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.

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.

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.

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).

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.