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Vitamin B2

Vitamin B2 or Riboflavin is a water-soluble vitamin that is part of the B group vitamins.

Vitamin B2 is found in very high levels in the kidney and liver. It is used by the body in a large variety of metabolic process and is important for the chemical reactions that produce energy for the body cells. Very little of this vitamin is stored by the body, so it needs to be replenished in the diet regularly. Certain medications can reduce the absorption of dietary Vitamin B2. These drugs include tricyclic antidepressant medications and antimalarial drugs such as quinacrine. Ultraviolet light destroys this vitamin, so Vitamin B2 deficiency can occur in young babies that have received ultraviolet light treatment for jaundice. Very large doses of oral Vitamin B2 do not produce any toxic effects because the body has a fairly limited capacity to absorb dietary forms of this vitamin.


Always consult your Health Professional to advise you on dosages and any possible medical interactions. Vitamin B2 is used medically to treat and prevent Vitamin B2 deficiencies. People who may benefit from Vitamin B2 include:

· Newborn babies treated for jaundice using phototherapy (ultraviolet light treatment).

· People with a poor diet, particularly those who consume moderate to large amounts of alcohol.

· Women on the contraceptive pill or on hormone replacement therapy.

Riboflavin may also assist in maintaining the strength of red blood cells (along with Folic acid). Supplementation with Vitamin B2 may be necessary in strict vegans, as B2 from vegetable sources is not as well absorbed as that from animal sources.


Vitamin B2 deficiency causes weakness, sore throat, oedema (fluid build up) in the pharynx and lining of the mouth, soreness and redness of the lips, tongue and mouth. The classic symptoms of too little Riboflavin are cracking of the lips and at the corners of the mouth. The skin around the nose, eyebrows and earlobes may begin to flake. Vision problems can occur with increased sensitivity to light and burning, tearing and itching of the eyes.


Major sources include milk, eggs, ice cream, liver, some lean meats and green vegetables.


The recommended dietary intake (RDI) for Vitamin B2 is 1.7 mg per day for adult men and 1.2 mg per day for adult women, although women that are pregnant require and additional 0.3 mg per day and those that are lactating require an additional 0.5 mg per day. The dosages required to correct deficiencies of Vitamin B2 are much higher. As for all the B vitamins, it is generally recommended that Vitamin B2 be taken as part of a B complex supplement to ensure the correct balance of B vitamins in the body.

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