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E171Avoid

Titanium dioxide

Group: Colours

Harm level5 of 5Avoid

In plain words

It is a white mineral pigment that gave foods a bright white, opaque look. It used to appear in sweets, chewing gum, icings and sauces, but it has been banned in food in the EU since 2022.

Where you find it: chewing gum, icings, sweets (outside EU), toothpaste

Our recommendation

Avoid it; watch especially for foods imported from outside the EU, where it may still be allowed.

Possible risks and effects

  • Damage to DNA (genotoxicity) cannot be ruled out.
  • Nanoparticles may accumulate in the body to a small extent.

For experts

Titanium dioxide (TiO2) is an inorganic pigment that includes a nanoparticle fraction. In 2021 EFSA concluded it could no longer be considered safe as a food additive because genotoxicity could not be ruled out, and set no ADI. The EU therefore banned it in food from August 2022; it is still used in medicines and cosmetics for now.

Check another E-number

More from this group

E102TartrazineE104Quinoline yellowE110Sunset Yellow FCFE122Azorubine (carmoisine)E124Ponceau 4RE129Allura Red ACE120Carmine (cochineal)E127Erythrosine

This information is educational and based on EFSA assessments and available studies; it does not replace medical advice. With allergies, intolerances or illness, follow your doctor’s advice.