Energy, mood and attention did not consistently improve with iron status in non‐anemic women with moderate to low iron stores

Abstract

Mood and attention were measured in a study to determine the bioavailability of iron (Fe) from heme, electrolytic, and reduced Fe, relative to placebo or FeSO4. In a randomized, blinded efficacy trial, 52 premenopausal, non-anemic women with moderate to low Fe stores received: a) placebo; b) 5 mg Fe as heme iron; or 50 mg Fe as c) electrolytic iron; d) reduced iron; or e) bakery-grade FeSO4, in 2 capsules and 3 wheat rolls/d, for 12 wk. The Profile of Mood States (POMS, BiPolar Form), Beck Depression Inventory II (BDI-II), and Conner’s Continuous Performance Test II (CPT II) were completed at admission, start, and end of treatments (wk 0, 5, 17). Body iron, based on serum transferrin receptor/ferritin ratio, increased with all Fe sources (mg/kg; LSM±SEM): FeSO4 (2.0±0.5, p<0.004), electrolytic (1.7±0.5, p<0.008), reduced (1.0±0.4, p<0.03), and heme (1.0±0.4, p<0.04), but not placebo (0.1±0.3, NS). However, fatigue scores (POMS) improved only with heme (6.0 units, p<0.02) and FeSO4 (3.1, p<0.04), not with reduced Fe (−0.7, NS), electrolytic Fe (−2.7, NS) or placebo (0.3, NS). Treatments did not affect other POMS, BDI-II or CPT II scores. By regression analysis, those with lower body iron had better attention scores at the start of treatment, which declined during the treatment period. However, changes in body iron did not predict changes in mood, depression, or attention. These results do not clearly indicate improved energy, mood or attention with improvements in iron status of non-anemic women. Funded by USDA-CREES grant 2002-35200-12222, Fe products from Proliant, Inc., and SUSTAIN.