Sakamoto N, Hu H, Nanri A, et al. - Using 2016 health checkup data from 36,422 diabetes-free workers, researchers looked at the relationship between hemoglobin A1c (HbA1c) and anemia, which was classified into three categories by mean corpuscular volume (MCV), as well as the link between hemoglobin in the nonanemic range and HbA1c. Anemic individuals are classified into three MCV-based groups: < 80, 80-90, and > 90 fL. Nonanemic individuals are classified into four groups based on their levels of hemoglobin. The authors discovered elevated HbA1c among anemic individuals with MCV < 80 fL or MCV 80-90 fL and reduced HbA1c among anemic individuals with MCV > 90, indicating that different types of anemia may affect HbA1c differently. In addition, nonanemic individuals with lower levels of hemoglobin had higher levels of HbA1c, indicating that hemoglobin levels need to be weighed when evaluating HbA1c values in nonanemic individuals.