Vitamin B2

Vitamin B2, also called riboflavin, is one of the 8 B vitamins. All the B vitamins are water-soluble, meaning that the body does not store them.

vitaminb2All B vitamins help the body convert food (carbohydrates) into fuel (glucose), which is “burned” to produce energy. These B vitamins, often referred to as B complex vitamins, also help the body metabolize fats and protein. B complex vitamins are necessary for healthy skin, hair, eyes, and liver. They also help the nervous system function properly.

In addition to producing energy for the body, riboflavin also works as an antioxidant by fighting damaging particles in the body known as free radicals. Free radicals can damage cells and DNA, and may contribute to the aging process, as well as the development of a number of health conditions, such as heart disease and cancer. Antioxidants such as riboflavin can fight free radicals and may reduce or help prevent some of the damage they cause.

Riboflavin is also needed to help the body change vitamin B6 (pyridoxine) and B9 (folate) into forms it can use. It is also important for body growth and red blood cell production. Most healthy people who eat a well-balanced diet get enough riboflavin. However, elderly people and alcoholics may be at risk for riboflavin deficiency because of poor diet. Symptoms of riboflavin deficiency include fatigue; slowed growth; digestive problems; cracks and sores around the corners of the mouth; swollen magenta-colored tongue; eye fatigue; swelling and soreness of the throat; and sensitivity to light.


The best sources of riboflavin include brewer’s yeast, hard goat cheese, almonds, organ meats, whole grains, wheat germ, wild rice, mushrooms, yogurt, eggs, broccoli, Brussels sprouts, and spinach.

Riboflavin is destroyed by light, so food should be stored away from light to protect its content. While it is not destroyed by heat, it can be lost in water when foods are boiled or soaked. During cooking, roasting, and steaming it preserves more riboflavin than any kind of frying.


It is best provided as riboflavin itself and no other identity. It is generally included in multivitamins and B-complex vitamins, and comes separately in 25-, 50-, and 100-mg tablets. Some medical grade riboflavin can be provided as high as 400mg in one capsule.


If you are currently being treated with any of the following medications, you should not use vitamin B2 supplements without first talking to your health care provider.

Anticholinergic Drugs – used to treat a variety of conditions, including gastrointestinal spasms, asthma, depression, and motion sickness. These drugs may make it hard for the body to absorb riboflavin.

Tetracycline – Riboflavin interferes with the absorption and effectiveness of tetracycline, an antibiotic. All vitamin B complex supplements act in this way. You should take riboflavin at a different time during the day from when you take tetracycline.

Tricyclic Antidepressants – Tricyclic antidepressants may reduce levels of riboflavin in the body. They include:
Imipramine (Tofranil)
Desimpramine (Norpramin)
Amitriptyline (Elavil)
Nortriptyline (Pamelor)

Antipsychotic Medications – Antipsychotic medications called phenothiazines (such as chlorpromazine or Thorazine) may lower riboflavin levels.

Doxorubicin – Riboflavin interferes with doxorubicin, a medication used for the treatment of certain cancers. Also, doxorubicin may deplete levels of riboflavin in the body. Your doctor will let you know whether you need to take a riboflavin supplement or not.

Methotrexate – Methotrexate, a medication used to treat cancer and autoimmune diseases such as rheumatoid arthritis, can interfere with how the body uses riboflavin.

Phenytoin – Phenytoin (Dilantin), a medication used to control seizures, may affect riboflavin levels in the body.

Probenecid – This medication used for gout may decrease the absorption of riboflavin from the digestive tract and increase how much is lost in the urine.

Thiazide Diuretics (water pills) – Diuretics that belong to a class known as thiazides, such as hydrochlorothiazide, may cause you to lose more riboflavin in your urine.


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