Vitamin B2
Vitamin B2 (or riboflavin) is a water-soluble vitamin (not stored in body fat) that is needed to activate flavoproteins, food enzymes that help release energy from carbohydrates, fats, and proteins. For the most part, this vitamin is absorbed in the upper digestive tract. Because it is yellow, riboflavin is also added to food in the form of E101 food color.
Roles
What does vitamin B2 do?
Vitamin B2 plays a critical role in helping the body:
- Generate energy;
- Produce red blood cells and hormones;
- Protect the nervous system and mucous membranes;
- Grow and repair tissue;
- Regulate muscle repair.
Needs
Recommended Dietary Allowances for Vitamin B2:
| By Age Group | | Recommended Dietary Allowance in mg/day |
| Children and teens | Ages 1 to 3 | 0.8 |
| Ages 3 and older | 1-1.6 | |
| Adults | Over 19 | 1.6 |
| Pregnant women | | 1.6 |
| Nursing mothers | | 1.6 |
Source: Manuel Pratique de Nutrition, L’alimentation préventive et curative, p. 68, 2009.
Sources
The primary food sources of riboflavin include milk and milk-based beverages, baked goods, and enriched cereals.
Food Sources for Vitamin B2:
| Foods | Portion Size | Vitamin B2 (mg) |
| Liver | 100g | 3-5 |
| Cheese, eggs | 100g | 0.3-0.45 |
| Mushrooms | 100g | 0.2 |
| Meat | 100g | 0.25-0.45 |
| Milk, yogurt | 100g | 0.15–0.2 |
| Asparagus, broccoli, Brussels sprouts, wholegrain bread | 100g | 0.15 |
Source: Manuel Pratique de Nutrition; L’alimentation préventive et curative, 2009.
Deficiency
Deficiency usually results when the diet is low in vitamin B2, and can lead to low vitamin B6 and niacin levels. Deficiency may also be caused when the body does not absorb vitamins properly. Vitamin B2 deficiency may be triggered or aggravated by certain medical conditions, namely:
- Cancer;
- Heart disease;
- Diabetes.
Some people may require more riboflavin, particularly those who have serious malabsorption problems or are undergoing dialysis, as well as women who are pregnant with multiples or nursing more than one infant.
Signs of vitamin B2 (riboflavin) deficiency:
- Sore throat;
- Inflammation and edema of the pharyngeal and oral membranes;
- Cheilitis (inflammation of the mucous membranes of the lips);
- Angular stomatitis (fissuring of the commissures of the lips);
- Shiny, red, dry, or cracked lips;
- Lacrimation (excessive or abnormal tearing of the eyes);
- Photophobia (abnormal light sensitivity in the eyes);
- Blood in the eye;
- Cataracts;
- Purple-colored tongue (glossitis);
- Seborrheic dermatitis (a skin ailment involving redness and scales, predominantly on the face);
- Stunted growth;
- Anemia.
Adverse effects
Elevated riboflavin levels, whether from diet or supplements, have not been associated with any substantive side effects. Large amounts of this insoluble vitamin, consumed orally, would appear to be relatively harmless because the body absorbs very little riboflavin in the digestive tract, quickly excreting it in urine.
Signs of excess vitamin B2 (riboflavin):
- None.
Cons-indications
- Children under 12 years of age or persons with kidney problems should not take riboflavin supplements.
Interactions
Natural health products and vitamin supplements:
- Psyllium (reduces absorption of vitamin B2).
Drugs:
- Extended use of probenicids, certain psychotropic medications, and antibiotics such as sulfa drugs may lead to vitamin B2 deficiency.
Additional information
Speak with your pharmacist if you plan to take vitamin B2 supplements. Your pharmacist can help you choose the solution that’s best for you based on your health and any drugs you take.
Other names
Vitamin B2, Riboflavin