E101 · Riboflavin, Riboflavin-5'-phosphate
- WHO
- Safe
- FDA
- Safe
- EFSA
- Safe
- FSANZ
- Safe
- Japan
- Safe
- UK FSA
- Safe
- Health Canada
- Safe
What is E101?
Riboflavin, also known as Vitamin B2, is an essential water-soluble vitamin used both as a nutrient additive and as a yellow-orange food colorant. It supports energy metabolism and is naturally found in eggs, milk, and leafy greens. Riboflavin-5'-phosphate is simply the phosphorylated (active) form used in the body and in some supplements. Both forms are considered safe food additives by EFSA and the FDA.
Also appears on labels as: Riboflavin, Riboflavin-5'-phosphate, Vitamin B2, Vit B2, VB2, Lactoflavin, E101, E 101, E-101, E101(i), E101(ii), Flavin mononucleotide.
What the evidence says
- Generally recognized as safe at typical food levels; it is a required vitamin, not a synthetic risk additive.
- May cause harmless bright yellow discoloration of urine at higher intakes.
Frequently asked questions
Is E101 safe?
Our overall verdict for E101 (Riboflavin, Riboflavin-5'-phosphate) is “Safe”, based on the most cautious of the major regulators’ positions — FDA: safe; WHO: safe; EFSA: safe; FSANZ: safe; Japan: safe; UK FSA: safe; Health Canada: safe.
Is E101 vegan, halal or gluten-free?
According to our ingredient data for Riboflavin, Riboflavin-5'-phosphate — vegan: yes, vegetarian: yes, halal: yes, kosher: yes, gluten-free: yes, dairy-free: yes. Manufacturing sources can vary between products; check the label if it matters to you.
What is E101 and why is it used?
Riboflavin, also known as Vitamin B2, is an essential water-soluble vitamin used both as a nutrient additive and as a yellow-orange food colorant. It supports energy metabolism and is naturally found in eggs, milk, and leafy greens. Riboflavin-5'-phosphate is simply the phosphorylated (active) form used in the body and in some supplements. Both forms are considered safe food additives by EFSA and the FDA.
Does E101 contain allergens?
No known allergens are recorded for Riboflavin, Riboflavin-5'-phosphate.
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This page summarises publicly available regulatory assessments and research. It is general information, not medical advice. Sources: EFSA, FDA, WHO and the studies linked above.