Share this page

Health Library

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.


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
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+1.1 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
  • Unusual skin inflammation (dermatitis) characterized by simultaneous dryness and greasy scaling
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, cooked3 ounces0.15 milligrams (mg)
Broccoli, cooked½ cup0.1 mg
Spinach, cooked½ cup0.21 mg
Milk, skim1 cup0.45 mg
Egg1 large0.26 mg
Whole wheat bread1 slice0.06 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
  • People with anorexia nervosa
Prevention of Cataracts

Evidence that links riboflavin to the prevention of cataracts is unclear. Two large studies showed decreases in cataract rates in people over 65 years taking multivitamins, minerals, riboflavin, and riboflavin with niacin. Although the studies showed decreased risk of cataracts, the mixing of the vitamins made it difficult to tell which supplement caused the benefits.

Treatment of Migraine Headaches

Talk to your doctor about using riboflavin supplements if you have migraine headaches. In some adults, 400 mg per day may prevent migraines or reduce the number of migraine attacks.

Tips for Increasing Your Intake

To help increase your intake of riboflavin, include some dairy products in your daily diet. Milk, yogurt, and cheese are all good sources of riboflavin. Here are some other examples of foods with riboflavin:

  • Eggs
  • Almonds
  • Leafy green vegetables
  • Milk
  • Enriched cereal
  • 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.


Academy of Nutrition and Dietetics

United States Department of Agriculture


Dietitians of Canada

Health Canada Food and Nutrition


Migraine prophylaxis in adults. EBSCO DynaMed website. Available at: Updated January 9, 2015. Accessed February 11, 2015.

Riboflavin. EBSCO DynaMed website. Available at: Updated January 8, 2013. Accessed February 11, 2015.

Riboflavin deficiency. EBSCO DynaMed website. Available at: Updated January 20, 2011. Accessed February 11, 2015.

Riboflavin. The Linus Pauling Institute website. Available at: Updated July 2013. Accessed February 11, 2015.

Sperduto RD, Hu TS, et al. The Linxian cataract studies. Two nutrition intervention trials. Arch Ophthalmol. 1993;111(9):1246-1253.

Vitamin B2. EBSCO Natural and Alternative Treatments website. Available at: Updated September 18, 2014. Accessed February 11, 2015.

Last reviewed February 2015 by Michael Woods, MD

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.

Baptist Flame

Health Library


Find A Doctor



Baptist Medical Clinic

Patients & Visitors


Contact Us

Physician Tools

Careers at Baptist

Employee Links

Online Services

At Baptist Health Systems

At Baptist Medical Center

close ×