Yılmaz S, et al. - Researchers conducted the study for analyzing the frequency of haematinic deficiencies (anemia, iron, folate, and vitamin B12 deficiency) and coeliac disease (CD) in children (n = 108) with recurrent aphthous stomatitis (RAS), characterized by recurrent and painful ulcerations on the nonkeratinised oral mucosa, and healthy children (n = 57) who were assessed for hematological abnormalities in routine evaluation. Compared with the control group, the frequency of a family history of RAS was significantly higher in the RAS group. In 32.4% of the RAS group and 10.5% of the control group, a hematological abnormality was identified. In the RAS group, iron deficiency anemia prevalence was significantly higher. Findings suggested that children with RAS should be assessed for the nutritional status and haematological indices, and CD screening should be considered in the case of haematological abnormalities and malnutrition.