Where to Find It
Best Form to Take
Riboflavin is the most commonly used supplement form of vitamin B2 and most clinical trials have used that form. The biologically active form of vitamin B2—riboflavin 5’-phosphate—is also commercially available, although most of it is converted into riboflavin in the intestine before being absorbed.24
How to Use It
The ideal level of intake is not known. The amounts found in many multivitamin supplements (20–25 mg) are more than adequate for most people.