. Riboflavin (vitamin B2)

Riboflavin is involved in energy production in three areas: 1) Glucose metabolism, 2) Oxidation of fatty acids, and 3) The shuttling of hydrogen ions through the Krebs cycle. Of particular interest to bodybuilders, Riboflavin is somewhat related to protein metabolism. In fact, there is a strong relationship between lean body mass and dietary riboflavin.
One study by Belko and colleagues found that females needed higher than RDA levels of Riboflavin to return blood levels of Riboflavin to normal after exercise. Another study by Haralambie showed that Riboflavin supplementation improved muscular hyperexcitability (seen in trained athletes). This vitamin may prove to be especially important for athletes.
Dear, Could you please describe some side effects of Riboflavin? I have taken Riboflavin by mouth then my urine to turn a yellow-orange color. My friend also affected by diarrhea while taking Riboflavin.