The current WHO cutoff levels were derived from mainly White adults37 but were validated in a multiethnic sample from a single country (US).22,23 The results of our multinational pooled fifth percentile Hb estimates were consistent with several studies10,12,13,14,15,38 that have called for a downward revision of the Hb cutoffs by approximately 1.0 g/dL for a variety of reasons, including a recent 2021 publication by Sachdev et al38 that suggests the use of lower Hb cutoffs to define anemia in children using data from the 2016 India Comprehensive National Nutrition Survey. This evidence concerns the gene GSTM1 and anemia (phenotype).