Energy restriction and iron supplementation improve iron status in women with obesity regardless of red meat consumption: a randomized controlled trial.

Iron deficiency without anemia (IDNA) may be linked to obesity-related inflammation. Weight reduction and heme-iron intake from red meat are proposed to improve iron status. This randomized controlled trial (NCT06104800) assessed the impact of a low-calorie, high-protein diet with red meat (RM) compared to a low-calorie, high-protein diet without red meat (WR) over 60 days on iron concentrations in women with obesity and IDNA receiving oral iron supplementation. Fifty-two females were randomized (26 per group); 45 completed the study. After intervention, serum iron increased for both groups: RM 55.8 ± 27.0 µg/dL to 69.8 ± 30.5 µg/dL, p = 0.05; WR 65.3 ± 28.4 µg/dL to 76.8 ± 45.6 µg/dL, p = 0.27. However, group-by-time analysis showed no significant differences between dietary interventions (p = 0.55). Additional significant improvements (p < 0.05) in secondary and exploratory outcomes included ferritin, transferrin, unsaturated iron-binding capacity, uric acid, and fat mass. In conclusion, no statistically significant benefit of red meat consumption over other dietary iron sources, when combined with oral iron supplementation, was demonstrated for improving iron status in women with obesity and IDNA.