Background: Female athletes and active adult females engaging in high volumes of exercise are at increased risk of compromised iron status due to heightened iron losses through menstruation, as well as exercise-induced mechanisms associated with physical training [1,2]. Oral iron supplementation is commonly employed in the prevention and/or treatment of iron deficiency but has been criticised because of associated side effects, such as constipation and increased risk of iron toxicity [1]. There is increasing interest in the use of food-based approaches, such as the prescription of an iron-rich and/or heme iron-based diet, for improving and maintaining iron status in females [3,4]. Therefore, the aim of the present study is to investigate the effects of increased lean red meat consumption on iron status in iron-deficient physically-active females in comparison to a habitual diet or an oral iron supplement (clinical trial registration: ISRCTN43345245). 

Methods: Physically-active iron-deficient non-anaemic females are randomly assigned at a ratio of 1:2:2 to either a control condition (CON), oral iron supplementation (SUPP), or an increase in lean red meat consumption (MEAT) for 12 weeks. Participants in the CON group maintain their habitual diet. Participants in the SUPP group consume their habitual diet with the provision of an oral iron supplement (325 mg of dried ferrous sulphate, equivalent to 105 mg elemental iron) ingested on alternate days for the intervention period. Participants in the MEAT group supplement their habitual diet with portions of lean red meat (170 g uncooked) consumed on alternate days for the intervention period. Iron status (hemoglobin, hematocrit, serum iron, serum ferritin, serum transferrin receptor, transferrin, transferrin saturation, total iron binding capacity), body composition (sum of 8 skinfolds, bioelectrical impedance analysis), dietary intake (4 day portion-estimate food diary), and subjective ratings of fatigue are measured before (week 0), during (weeks 4 and 8) and after (week 12) the intervention period. 

Results: Preliminary results (CON, n=4; SUPP, n=7; MEAT, n=5) show similar baseline values for iron status across all 3 groups, with serum ferritin concentrations of 27.3 ±13 ng/mL, 21.3 ±10.4 ng/mL, and 25.4 ±10.9 ng/mL for CON, SUPP and MEAT, respectively. Serum ferritin concentrations are unchanged in CON, but are increased directionally by week 8 in SUPP and MEAT. Recruitment for this study is ongoing with an expected completion date of June 2024. 

Conclusion: This study is investigating the effects of increased lean red meat consumption on iron status in iron-deficient physically-active females. Preliminary results indicate that this food-based approach has the potential to improve iron status in a similar magnitude to iron supplementation in this population.