Moderate iron deficiency and physical training affect body fat accretion in growing male rats

Abstract

Recent human studies demonstrate a relationship between iron deficiency and obesity, but it is not known whether physical training (PT) modulates the effects of iron deficiency on body composition and fat accretion. The objective of this study was to determine whether the effects of moderate iron deficiency on body fat accretion would be modulated by PT in growing rats. Male Sprague‐Dawley rats were fed iron adequate (IA, 45 mg/kg) or moderately iron deficient (ID, 10 mg/kg) diets ad libitum for 12 wks. Rats were assigned to four treatment groups (n = 10 per group): IA sedentary (IAS), IA physically trained (IAPT), ID sedentary (IDS), or ID physically trained (IDPT). PT involved running on motorized running wheels at 4 M/min for 1 h/d for 5 d/wk. After 12 wks, ID rats were not anemic, but iron status was diminished, as indicated by increased (P < 0.05) red cell distribution width ([mean ± SD] IAS = 13.8 ± 0.9, IAPT = 13.8 ± 1.1, IDS = 15.1 ± 0.5, IDPT = 14.1 ± 0.8 %). Body weight, lean body mass, and bone mineral content did not differ between groups. In contrast, the IDS rats had greater (P < 0.05) body fat as compared to all other groups (IAS = 31.8 ± 2.9, IAPT = 31.8 ± 2.0, IDS = 38.6 ± 6.7, IDPT = 32.8 ± 4.5 %). Thus, moderate iron deficiency may increase body fat accretion in growing animals, and PT appears to attenuate that effect. Research supported by MRMC.