Riboflavin

Riboflavin, also known as vitamin B2, is an essential nutrient that your body uses to convert food into energy and support cell growth and metabolism. A blood riboflavin test measures the level of this vitamin circulating in your bloodstream. Deficiency is uncommon in developed countries but can occur with malabsorption disorders, certain medications, or restrictive diets. Low levels may cause fatigue, mouth sores, or skin issues. This test is typically ordered when nutritional deficiency is suspected or to monitor patients at risk.