Dietary factors associated with the risk of high iron stores in the elderly Framingham Heart Study cohort

Abstract

Background: High body iron stores may increase the risk of several chronic diseases. Whether dietary factors contribute to the risk of high iron stores is unknown. Objective: We assessed the relation between dietary factors and the risk of high iron stores in the elderly Framingham Heart Study cohort. Design: We examined the relation between the usual intake of dietary factors (food-frequency questionnaire) and the risk of high iron stores (serum ferritin > 300 and 200 μg/L in men and women, respectively) in 614 subjects aged 68-93 y. Results: The risk of high iron stores was significantly higher I) in subjects who took ≥ 30 mg supplemental Fe/d than in nonusers [odds ratio (OR): 4.32; 95% CI: 1.63, 11.47], 2) in subjects who consumed > 21 servings of fruit/wk than in those who consumed ≤ 14 servings/wk (OR: 2.88; 95% CI: 1.26, 6.61), and 3) in subjects who consumed > 4 but < 7 or ≥ 7 servings of red meat/wk than in those who consumed ≤ 4 servings/wk (ORs: 2.94 and 3.61, respectively; 95% CIs: 1.33, 6.47 and 1.57, 8.27, respectively). Whole-grain intake (> 7 servings/wk) was inversely associated (OR: 0.23; 95% CI: 0.07, 0.75). Conclusions: Among elders, intakes of highly bioavailable forms of iron (supplemental iron and red meat) and of fruit, a dietary source of an enhancer of nonheme-iron absorption (vitamin C), promote high iron stores, whereas foods containing phytate (whole grains) decrease these stores. Individual dietary patterns may be important modulators of high iron stores.