Riboflavin, or vitamin B-2, occurs in all of the food groups, but deficiencies can develop and result in symptoms that affect your mouth, eyes and skin. You can get plentiful riboflavin in dairy products, whole grains and dark green leafy vegetables, such as broccoli, turnip greens, asparagus and spinach. It also occurs in grains, fruits, legumes, nuts, seeds, meats and nutritional yeast. Breads and cereals may be fortified with riboflavin and it is commonly included in multivitamins or vitamin B-complex dietary supplements. Because it is water soluble and not stored in your body, you must replenish it frequently.
Riboflavin serves as a coenzyme and works with other B vitamins in many reactions to release energy from nutrients in your body's cells by accepting and then donating two hydrogens, according to Eleanor Whitney and Sharon Rolfes in "Understanding Nutrition." Riboflavin also assists with growth and the production of red blood cells.
Ultraviolet light and irradiation destroy riboflavin. Do not store foods with riboflavin in glass containers that are exposed to light. The riboflavin in milk is protected by storage in cardboard or opaque plastic containers and precautions are taken to protect the riboflavin when vitamin D is added to milk by irradiation, according to "Understanding Nutrition." Cooking does not destroy riboflavin; it is stable to heat. Riboflavin that is not needed leaves the body through the urine.
No disease is associated with riboflavin deficiency, but it causes inflammation of the membranes of your mouth, skin, eyes and gastrointestinal tract. It results in a sore throat and cracks and redness at the corners of your mouth. Symptoms of a deficiency include swelling of mucous membranes, sores on your lips or mouth and skin disorders. Symptoms in your eyes can include inflamed eyelids, sensitivity to light and reddening of your cornea.
Deficiency of riboflavin is uncommon in the United States since it is plentiful in the food supply and your body needs only a modest amount. Severe riboflavin deficiency may affect many enzyme systems because it is needed in the metabolism of vitamin B-6, niacin and folic acid, as reported by the Linus Pauling Institute. Vegans and other persons who do not drink milk can rely on generous servings of dark green vegetables and enriched grains for most of their riboflavin. Other persons at risk for riboflavin deficiency include anorexic persons who do not consume enough nutrients in general and alcoholics who have decreased intake, absorption and utilization of riboflavin.
Avoid nutrient deficiencies by eating a variety of foods as part of a balanced diet that provides your daily requirement of essential vitamins, including riboflavin. The Recommended Daily Allowances, RDAs, for riboflavin range from 0.3 mg per day for infants to 1.3 mg per day for adult males. Specific recommendations vary by age, gender and life cycle stage, such as pregnancy and lactation. Ask your doctor or dietitian what amount fits your health needs.