Vitamin B2 , also called riboflavin, is a water-soluble vitamin. Water-soluble vitamins are stored in the body in very limited amounts and are excreted through the urine. Therefore, it is a good idea to have them in your daily diet. Vitamin B2 is a component of two enzymes: flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). These coenzymes are important in energy production.

Functions

Riboflavin’s functions include:

  • Assisting in energy production
  • Helping to synthesize normal fatty acids and amino acids
  • Helping the nervous system to function efficiently
  • Aiding in cellular growth
  • Assisting in the metabolism of certain other vitamins

Recommended Intake

Age Group (in years)Recommended Dietary Allowance
FemalesMales
1-30.5 milligrams (mg)0.5 mg
4-80.6 mg0.6 mg
9-130.9 mg0.9 mg
14-181.0 mg1.3 mg
19-701.1 mg1.3 mg
Pregnancy1.4 mgn/a
Lactation1.6 mgn/a

Riboflavin Deficiency

Riboflavin deficiency occurs as part of multiple nutrient deficiency states. Since riboflavin occurs in a wide variety of foods, deficiency symptoms are rare. Symptoms have been reported when daily riboflavin intake falls below 0.6 milligrams (mg). Symptoms of riboflavin deficiency include:

  • Cracks in the corner of the mouth (cheilosis)
  • Inflammation of the mucous membranes of the mouth
  • Sore or inflamed tongue (glossitis)
  • Reddening of the eyes
  • Eyes that tire easily, burn, itch, or are sensitive to light
  • Dimming of vision
  • Unusual skin inflammation (dermatitis) characterized by simultaneous dryness and greasy scaling
  • Depression , hysteria, or other psychiatric problems caused by nerve tissue damage or decreased neurotransmitter production
  • Malformations and retarded growth in infants and children

Riboflavin Toxicity

Riboflavin is relatively nontoxic. Although no adverse effects have been associated with high intakes of riboflavin from food or supplements, the potential may exist. Therefore, caution may be warranted with excessive amounts of riboflavin.

Major Food Sources

FoodServing sizeRiboflavin content
Beef liver, braised3 ounces3.5 milligrams (mg)
Yogurt, skim with dry milk solids1 cup1.6 mg
Broccoli, cooked1 2/3 cups0.5 mg
Spinach, cooked1 1/3 cups0.5 mg
Milk, skim1 cup0.4 mg
Enriched corn tortilla1 tortilla0.2 mg
Egg1 large0.1 mg
Whole grain bread1 slice0.1 mg

Health Implications

Populations at Risk for Riboflavin Deficiency

The following populations may be at risk for riboflavin deficiency and may require a supplement:

  • People who consume excessive amounts of alcohol
  • People with other nutrient deficiencies
  • Infants with jaundice who are treated with specialized light therapy
  • People with anorexia nervosa
  • Individuals who avoid dairy products
  • Malabsorption ( celiac disease , malignancy, etc)
  • Long term use of barbiturates (eg, phenobarbital)

Prevention of Cataracts

Several studies have suggested that riboflavin may play a role in the prevention of cataracts ; however, further studies are needed to confirm this relationship.

Treatment of Migraine Headaches

Preliminary findings from a randomized placebo-controlled trial suggested that riboflavin supplementation might be a useful in addition to beta-blockers to help prevent migraine headaches .

Tips for Increasing Your Intake

To help increase your intake of riboflavin:

  • Include dairy products in your daily diet, such as milk, yogurt, and cheese.
  • Eat foods rich in riboflavin, such as:
    • Liver
    • Mushrooms
    • Leafy green vegetables
    • Eggs
    • Enriched bread, rolls, and crackers
    • Meats

Riboflavin is rapidly destroyed with exposure to sunlight. Therefore, foods containing riboflavin are best stored in a pantry, in bins, and, when perishable, in the refrigerator.