Vitamin B2 

avitaminosis caused by lack of thiamine (vitamin B1)

Riboflavin (E101), also known as vitamin B or vitamin G, is an easily absorbed, water-soluble micronutrient with a key role in maintaining human health. Like the other B vitamins, it supports energy production by aiding in the metabolising of fats, carbohydrates, and proteins. Vitamin B is also required for red blood cell formation and respiration, antibody production, and for regulating human growth and reproduction. ...

Beriberi as related to Riboflavin