Effects of consuming an iron‐biofortified bean on behavioral and electrophysiological measures of attention

Abstract

Iron deficiency (ID) can produce deficits in cognition and brain dynamics, and repletion may reverse these changes. We conducted a double‐blind efficacy study involving healthy female students (n = 239) screened for low iron status. Participants were randomized to groups that consumed either a high‐iron‐biofortified (BB) or a normal‐iron bean (CN) for 20 weeks. A subsample (n = 53) performed cognitive tasks while concurrent EEG was acquired at baseline (BL), endline (EL), and at one of eight random time‐points in between. Cognitive tasks included (a) a measure of perceptual speed (simple reaction time, SRT); (b) a test of inhibitory control (go/no‐go, GNG); and (c) an assessment of three aspects of attention (attentional network task, ANT). Small but significant improvements from BL to EL were observed for hemoglobin, ferritin, and total body iron, with larger improvements for the BB vs CN group. Behaviorally, there were no improvements in the SRT, possibly reflecting a floor‐effect. Significant condition (BB, CN) x time interactions were obtained for the behavioral measures from the GNG and ANT. The EEG data revealed significant differential increases for the BB vs CN group in the amplitudes of two components (N1 and P2), and normalized spectral power in two frequency ranges (alpha and gamma) that index aspects of attention in all three tasks. The results suggest that consuming BB may benefit behavior and brain function.