Vitamin B2 or riboflavin, also known as vitamin G, is essential for growth and general health as also for healthy eyes, skin, nails and hair. It helps eliminate sore mouth, lips and tongue. It also functions with other substances to metabolis carbohydrates, fats, and protein. The main sources of this vitamin are green leafy vegetables, milk, cheese, wheat germ, egg, almonds, sunflower, seeds, citrus fruits and tomatoes. Its deficiency can cause a burning sensation in the legs, lips and tongue, oily skin, premature wrinkles on face and arm and eczema.

The recommended daily allowance for this vitamin is 1.6 to 2.6 mg. for adults and 0.6 to one mg for children. Its use in larger quantities, say from 25 to 50 mg. is beneficial in the treatment of nutritional cataracts and other eye ailments, digestive disturbances, nervous depression, general debility, and certain types of high blood pressure.

Riboflavin (vitamin B2) is manufactured in the body by the intestinal flora and is easily absorbed, although very small quantities are stored, so there is a constant need for this vitamin.

Vitamin B2 - riboflavin - is required for

It is required by the body to use oxygen and the metabolism of amino acids, fatty acids, and carbohydrates. Riboflavin is further needed to activate vitamin B6 (pyridoxine), helps to create niacin and assists the adrenal gland. It may be used for red blood cell formation, antibody production, cell respiration, and growth.
It eases watery eye fatigue and may be helpful in the prevention and treatment of cataracts. Vitamin B2 is required for the health of the mucus membranes in the digestive tract and helps with the absorption of iron and vitamin B6.
Although it is needed for periods of rapid growth, it is also needed when protein intake is high, and is most beneficial to the skin, hair and nails.

Deficiency of vitamin B2

A shortage of this vitamin may manifest itself as cracks and sores at the corners of the mouth, eye disorders, inflammation of the mouth and tongue, and skin lesions.
Dermatitis, dizziness, hair loss, insomnia, light sensitivity, poor digestion, retarded growth, and slow mental responses have also been reported. Burning feet can also be indicative of a shortage.

Dosage

The dosage underneath is the Recommended Dietary Allowance (RDA), but be aware that this dosage is the minimum that you require per day, to ward off serious deficiency of this particular nutrient. In the therapeutic use of this nutrient, the dosage is usually increased considerably, but the toxicity level must be kept in mind.
Male 1,6 mg per day and female 1.2 mg per day although 50 mg is mostly recommended for supplementation.

Toxicity and symptoms of high intake

The limited capacity to absorb orally administered riboflavin precludes its potential for harm. Riboflavin intake of many times the RDA is without demonstrable toxicity.
A normal yellow discoloration of the urine is seen with an increased intake of this vitamin - but it is normal and harmless.

Best used with

Riboflavin is best taken with B group vitamins and vitamin C.
But please note - if taking a B2 supplement make sure that the B6 amount is nearly the same.

When more may be required

Extra might be needed when consuming alcohol, antibiotics, and birth control pills or doing strenuous exercise.
If you are under a lot of stress or on a calorie-restricted diet, this vitamin could also be of use.

Enemy of nutrient of vitamin B2

Riboflavin is sensitive to light.

Other interesting points

This nutrient is of use in the health of hair, nails and skin.

Food sources of vitamin B2

Organ meats, nuts, cheese, eggs, milk and lean meat are great sources of riboflavin, but is also available in good quantities in green leafy vegetables, fish, legumes, whole grains, and yogurt.