Vitamin (water-soluble)

• UK RNI 1.3 mg
• US RDA 1.7 mg

Functions

• Activates vitamin B6
• Conversion of carbyhydrate to energy
• Conversion of tryptophan to vitamin B3
• Growth
• Metabolism of fats, protein and carbohydrate

Good food sources

• Dairy produce
• Eggs
• Liver
• Meat
• Soya flour
• Whole grains

Deficiency symptoms

• Bloodshot, burning, 'gritty' eyes
• Cracks and sores in corners of mouth
• Dryness, cracking, peeling of lips
• Eyes sensitive to light
• Insomnia
• Sides of nose red, greasy and scaly
• Soreness and burning of lips and tongue

Low levels of several B vitamins have been found in psychiatric patients and in senile dementia.

Preventing deficiency

See Vitamin B1. The bioavailability of Vitamin B2 is reduced by the consumption of alcohol, and by high zinc levels, some antibiotics, and caffeine. Riboflavin in foods is destroyed by lengthy exposure to the light. Up to 14 per cent of vitamin B2 is lost when milk is pasteurized, and a further 12-25 per cent when it is boiled.

Comments

See Vitamin B1.

SUPPLEMENTATION

In research studies, Vitamin B2 supplements have been found to help against:

• Acne rosacea
• Carpal tunnel syndrome
• Cataracts
• Mitochondrial myopathies
• Some types of anaemia

Preferred form and suggested intake

See Vitamin B1.

Cautions

See Vitamin B1. There is no known unsafe dosage of vitamin B2. Yellow colouration of urine after taking B complex supplements containing vitamin B2 is harmless.