Vitamin B2 (Riboflavin)

Description Riboflavin is water soluble and part of the B-vitamins group.
Function/ Used for Riboflavin is essential for the formation of two substances: FAD (flavin adenine dinucleotide) and FMN (flavin mononucleotide). Both are vital for the processes that make energy available in the body. Riboflavin works effectively with iron, vitamin B6 and folic acid. It is important for the nervous system, skin and eye health.

It also helps keep red blood cells healthy, protects cells from oxidative stress and helps reduce tiredness and fatigue.

Intake Recommended intake

EU NRV: 1.4mg


UK average daily intake

Requirements vary depending on age and gender. The UK National Diet and Nutrition Survey lists up-to-date intake requirements and average intakes1.

As a supplement Not generally available as a single supplement. Commonly available as part of a multivitamin and mineral formula.

Different multivitamin and minerals products will vary in the percentage NRVs they include. People should always check the label for information about a specific product.

Found in (dietary sources) Liver, kidneys, fortified breakfast cereals, meat, milk, some green vegetables, eggs, cheese, yeast extracts.

Riboflavin is degraded by heat and also exposure to light. This is significant with respect to milk, which is a major source of riboflavin (i.e. if milk is exposed to bright sunlight/light for long periods of time).

Deficiency Trembling, dizziness, poor concentration and memory. Also, blood-shot, red, tired or gritty eyes; Mouth ulcers or sores and cracks at the corner of the mouth; Red, inflamed tongue and lips and scaly eczema-like skin rash.3
Precautions and contraindications Safe Upper Level: 40mg/day2
Use in pregnancy and breastfeeding There is no evidence of adverse effects in pregnancy.
Interactions e.g. with other medications Excessive alcohol intake induces riboflavin deficiency.

Prolonged use of oral contraceptives may induce riboflavin deficiency.

Deficiency of riboflavin may impair iron metabolism and produce anaemia.

Adequate amounts of all B vitamins are required for optimal functioning; deficiency or excess of one B vitamin may lead to abnormalities in the metabolism of another.3


Adverse effects None known, although large doses may cause a yellow discolouration of the urine.
References 1.

2         Expert Group on Vitamins and Minerals, 2003.

3         Mason, P. Dietary Supplements