Vitamin B2 (Riboflavin)

Vitamin B2, also known as riboflavin, is a yellow-orange substance with relatively low solubility in water. It is essential for a vast range of oxidative processes that sustain oxygen-dependent life forms and also has vital roles in the formation and activation of several other vitamins, including vitamin A, vitamin B3, and folate. Dairy products such as milk and cheese are good dietary sources of riboflavin, in addition to liver, yeast, mushrooms and almonds. 


Functions

The active forms of vitamin B2, flavin adenine dinucleotide (FAD) and flavin mononucleotide (FMN), act as co-factors for a number of flavin-dependent enzymes integral to the production of cellular energy and for the formation and activation of vitamins such as retinoic acid and niacin.  Riboflavin is also crucial for optimal growth and development and is involved in red blood cell production. 

Reference Intake (RI)


   AGE

   CHILDREN

    MALES

FEMALES

MALES

FEMALES

PREGNANCY

YEARS

1-3

4-6

7-10

11-14

15-17

11-14

15-17

18-64

65+

18-64

65+

 

VITAMIN B2 (mg / day)

0.6

0.8

1.0

1.2

1.3

1.1

1.1

1.3

1.3

1.1

1.1

       (+0.3)

 

    MONTHS

0-3

4-6

7-9

10-12

LACTATION

VITAMIN B2 (mg / day)

0.4

0.4

0.4

0.4  

       (+0.5)

 

Food Sources

PRODUCTS

Cheese (Gjetost)

     Almonds

Liver (Lamb)

Oily Fish (Mackerel)

(mg / 100 g)

1.38 

1.1 

3.6 

0.58 

PRODUCTS

Egg (hard boiled)

Pork   

Sesame Seeds  

Seafood (Squid)

   (mg / 100 g)

0.51

0.51 

0.47 

0.46 

 

Deficiency / Toxicity

Riboflavin deficiency can appear at intakes of less than 0.5 – 0.6 mg / day and is often associated with concurrent deficiency of other water-soluble vitamins. In addition to inadequate dietary intake, secondary deficiency may also occur due to intestinal malabsorption, resistance, or increased excretion, and due to the presence of clinical conditions such as diabetes, heart disease, or HIV infection. Inadequate riboflavin status can result in;

  • Throat swelling or soreness
  • Skin cracking (generally seen more around the corners of the mouth)
  • Burning or gritty eyes 
  • Blurred vision
  • Anaemia 


Due to it's relatively low solubility, absorption of riboflavin into the circulation in sufficient amounts to induce toxic effects is considered unlikely.