Vitamin B2 is sensitive to cooking and lost in cooking water. It is also sensitive to light. In order to protect it, foods should be stored away from light and it is preferable to purchase fresh products.
It has a role in energy release from foods (supports a normal energy metabolism) and in maintaining normal skin and eyesight.
Vitamin B2 or riboflavin is water-soluble and characterised by its yellow colour.
It is relatively insensitive to heat as it is broken down from high temperatures (285°C). However, riboflavin is sensitive to light.
It is one of the rare vitamins to be produced by the body (in the gut flora); however, the amounts produced are insufficient to meet the body's requirements. Dietary sources are therefore necessary.
Considerable uptake takes place in the upper part of the small intestine, but practically no reserves are stored, meaning that daily dietary intake is necessary. Excess B2 is excreted in urine and is responsible for its yellow colour.
Roles
Vitamin B2 has many roles in the body: riboflavin acts as a coenzyme or enzyme prosthetic group in many redox reactions.
Energy release : vitamin B2 is involved in the general metabolism of carbohydrates, fat and protein and more particularly in the oxidation of glucose, causing energy release.
Cellular respiration : riboflavin is involved at a cellular level (mitochondria) in breaking down the components of food. This breakdown results in the production of a substance suitable for use for cell function.
Vitamin B2 helps maintain normal skin.
Requirements
Requirements are higher for pregnant and breastfeeding women. Caution, deficient intake during pregnancy increases the risk of birth defects. However, although sufficient amounts are necessary during these two periods, excessive doses of vitamin B2 should be avoided.
For infants, breast milk is a sufficient source for their requirements.
Table of RNI (Reference Nutrient Intakes) for vitamin B2 :