Vitamin B12 and recurrent aphthous stomatitis

The letter raises two points about a previous study that investigated possible etiological factors of recurrent aphthous stomatitis (RAS), including vitamin B12 deficiency. First, the letter questions whether the vitamin B12 and hematological results of the study are reliable, as 35% of subjects were B12 deficient but mean hemoglobin and hematocrit levels did not indicate anemia. Second, the letter asks why mean corpuscular volume, an important indicator for B12 deficiency, was not reported. The authors of the original study respond that their laboratory tests and results are reliable, vitamin B12 levels were not low enough to cause anemia, and they purposely did not report mean corpuscular volume to avoid confusing readers