Riboflavin, also known as vitamin B2, is a water-soluble vitamin that is naturally present in many foods. It plays a key role in energy production and metabolism and helps maintain healthy skin, hair, eyes and liver. Good dietary sources of riboflavin include eggs, meat, dairy products, legumes, nuts and green leafy vegetables. Deficiency can cause health problems like cracks in the lips or mouth, inflammation of the tongue, and sensitivity to light.

6. http://www.kr.ac.th/tech/det48m2/f008.html
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