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Vitamin B2

WATER-SOLUBLE

Flavin adenine dinucleotide (FAD), Flavin mononucleotide (FMN)

Riboflavin (vitamin B2) serves as the precursor for two essential coenzymes — FAD and FMN — that participate in oxidation-reduction reactions throughout cellular metabolism. These are prosthetic groups for approximately 100 human enzymes (flavoproteins) involved in energy production, antioxidant defense, and fatty acid oxidation. Riboflavin is also required for the conversion of tryptophan to niacin and the activation of vitamin B6.

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Key Functions

  • Energy production via FAD/FMN coenzymes
  • Antioxidant function (glutathione reductase)
  • Cellular growth and development
  • Red blood cell formation
  • Conversion of B6 and folate to active forms

Best Food Sources

Dairy products and eggsLean meats and organ meatsAlmonds and mushroomsSpinach and fortified grains

Deficiency: Ariboflavinosis

  • Cracked lips (cheilitis)
  • Inflammation of the tongue (glossitis)
  • Redness at corners of mouth (angular stomatitis)
  • Sore throat
  • Sensitivity to light

High-Risk Groups

  • People on restricted diets
  • Those with thyroid disorders
  • Chronic alcoholics

Reviewed for accuracy: Content is based on guidelines from the NIH Office of Dietary Supplements, Harvard T.H. Chan School of Public Health, and peer-reviewed medical literature.

Recommended Daily Amount

Adult Men

1.3 mg

Adult Women

1.1 mg

Did You Know?

Riboflavin is light-sensitive — milk stored in transparent containers can lose significant riboflavin through photodegradation.

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