Ariboflavinosis, riboflavin deficiency, is a rare condition that often occurs with other nutrient deficiencies. The symptoms of this condition are shown in the figure below.
The most notable symptoms include angular stomatitis (aka angular cheilitis, like cheilosis), which is a lesion that forms at the corners of the mouth as shown below.
Glossitis is the inflammation of the tongue, which can be accompanied by redness or inflammation of the oral cavity. Dermatitis is also frequently a symptom3,4.
There has been no toxicity of riboflavin reported.
References & Links
1. http://www.fao.org/docrep/W0073e/p206.gif
2. http://en.wikipedia.org/wiki/File:Angular_Cheilitis.JPG
3. Gropper SS, Smith JL, Groff JL. (2008) Advanced nutrition and human metabolism. Belmont, CA: Wadsworth Publishing.
4. Byrd-Bredbenner C, Moe G, Beshgetoor D, Berning J. (2009) Wardlaw’s perspectives in nutrition. New York, NY: McGraw-Hill.