LIFESTYLE AND DIETARY PRACTICES INFLUENCING IRON STATUS IN UNIVERSITY WOMEN

Abstract

Lifestyle and dietary factors influencing iron status were studied in 80 university women (ages 19–26, 98% caucasian) who indicated interest in nutrition and/or health (48% were dietetics majors). Included were factors such as smoking, oral contraceptive use, and vitamin/mineral supplementation, which are common practices, but often excluded in studies of diet and iron status. Usual dietary intake was estimated using the Block-National Cancer Institute Health Habits Questionnaire (Full'87). Iron depletion (serum ferritin > 15 μg/L) was present in 34%, elevated total iron binding capacity (> 63 μmol/L) in 67%, and 5 (6%) of the women were anemic with iron deficiency. Red meat (beef, pork, lamb) was consumed ≥ 3 times per week in 26%; 0.75–1.25 times per week in 51%; and never in 24% of the subjects. Heme iron intake was not significantly different between the red meat groups, but total iron intake (including supplements) was greatest (p<0.05) in red meat abstainers. Total iron intake was positively related to hemoglobin and hematocrit in red meat eaters, but not abstainers (p<0.05). Red meat intake did not significantly influence serum ferritin concentrations. Multiple regression analysis identified total iron intake (including supplement intake), smoking and frequent dieting to lose weight as the predominant factors influencing serum ferritin concentration (R2 = 0.62, p<0.0001). Factors such as exercise and intakes of heme iron, dietary iron, energy, vitamin C, fiber, and alcohol did not influence any parameters of iron status. None of the factors studied significantly influenced transferrin saturation. Oral contraceptives and blood donation were associated with elevated iron binding capacity, whereas, supplement use was related to lower levels (R2 =0.33, p < 0.0001). In the present group of women with a high prevalence of iron deficiency, total iron intake, habitual dieting for weight loss, and smoking rather than red meat consumption were key determinants of iron status.Copyright © 1996 Elsevier Science Inc.