Vitamin B2
Riboflavin supports energy production and cell function.
The formula matches the form shown in the 3D model. Other forms of this vitamin can have different formulas.Loading molecular structure…
Riboflavin · Drag to rotate
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One representative form. Hydrogens omitted; bonds simplified.
PubChem · CID 493570Where you can find it
- Milk
- Eggs
- Almonds
- Mushrooms
- Fortified cereals
What it does in the body
Riboflavin helps enzymes release energy and process fats and other nutrients.
Recommended amounts & upper limit
US reference values for healthy adults aged 19–50, excluding pregnancy and breastfeeding. These are daily dietary intakes, not blood-test ranges or prescribed supplement doses. Other ages and life stages have different needs; see the original source.
- Men · RDA
- 1.3 mg/day
- Women · RDA
- 1.1 mg/day
- Upper limit · UL
- No established ULInsufficient evidence of harm to establish a UL; high doses are not automatically beneficial.
How to read these levels
RDA means Recommended Dietary Allowance; AI means Adequate Intake, used when an RDA cannot be set. The upper limit (UL) is not a target or an exact toxicity threshold. Going below the RDA on one day does not diagnose deficiency. No established UL does not mean unlimited amounts are safe.
mg = milligrams; mcg = micrograms. 1 mg = 1,000 mcg. IU is vitamin-specific and cannot be converted with one rule for all vitamins.
What happens when the balance changes?
These are possible effects, not a diagnosis or a prediction from one low or high result.
Too little
Can cause cracked lips, sores at mouth corners, sore throat, skin changes and red, itchy eyes. Severe prolonged deficiency can contribute to anaemia.
Body areas affected
Mouth, skin, eyes and blood.
Too much
No clear toxicity from high oral intake has been established. Evidence is limited rather than proof of unlimited safety.
Body areas affected
No specific organ toxicity established.
What about blood-test levels?
Blood-test levels and daily intake use different units and cannot be compared directly. Test methods, reference ranges and clinical context vary. Symptoms alone cannot establish a vitamin deficiency or toxicity; a clinician can decide which tests and treatment are appropriate.
The body connection
Deficiency often affects the mouth, skin and eyes.
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