E171 (titanium dioxide)

E171 is titanium dioxide, a white mineral colour and opacifier formerly used in foods to provide whiteness, opacity and a dense visual appearance. It could be found in icing, candies, chewing gum, decorative coatings, capsules and products needing a bright white background. For the European market, it is now important to describe it not as an ordinary permitted colour, but as an additive whose status has changed.

In 2021, EFSA reassessed the safety of titanium dioxide as a food additive and concluded that E171 could no longer be considered safe when used in food. The key reason was that a concern for genotoxicity of TiO2 particles could not be ruled out. Regulation (EU) 2022/63 then removed the authorisation to use E171 in foods in the EU. Older texts that describe it simply as a white colour are therefore no longer sufficient.

Why it was used

Titanium dioxide gave foods opacity and a clean white colour. In confectionery it helped make icing dense, hide the colour of the base or create contrast with other dyes. In chewing gum and coated sweets it provided a matte, uniform coating. In capsules and tablet-like forms, white colour made products look clean, standardised and precise.

The food role of E171 was always technological. It did not add flavour, protein, minerals or satiety. White colour could create an impression of cleanliness, freshness or pharmaceutical precision, but that was a visual signal. Nutritionally, such a signal can be misleading: white icing or a capsule may look neutral, while sugar, starch, flavourings or other more important ingredients are present.

What changed in safety assessment

EFSA’s updated assessment considered data on titanium dioxide particles, including nanoparticles, and modern approaches to genotoxicity evaluation. The conclusion was not that every product with E171 had been proven to cause a specific harm. It was more precise and more cautious: a concern for genotoxicity could not be excluded, and a safe level of daily intake could not be established.

This is why E171 differs from most colourants in this group. For many additives the discussion is about ADI, dose, tolerance and the surrounding product. For E171, food authorisation in the EU was removed. If someone sees E171 in an imported product, an old label, a supplement or a non-EU food, the current status, product category and jurisdiction need to be checked. Cosmetics, medicines and foods are regulated differently.

Relevance for LCHF and keto

E171 is not a carbohydrate, but that does not make it an acceptable detail of a low-carbohydrate diet. The issue here is not sugar but food-additive safety and regulatory status. A product may be formally low in carbohydrate and still contain a component no longer authorised as a food additive in the EU. Assessment must therefore go beyond the macronutrient table.

In practice, E171 often appeared in products that rarely form a good LCHF base even without it: sweet coated candies, icing, chewing products, decorative desserts and capsules with questionable formulas. Even when sugar is replaced with sweeteners, the product may remain ultra-processed and sensory-heavy. White colour should not create an impression of safety or purity.

What a shopper should do

If a food label lists E171, titanium dioxide or TiO2, the product deserves a critical look. In the EU this is especially important because food use authorisation has been removed. Products from other countries may follow different rules, but from a cautious nutrition perspective there is no reason to seek foods containing E171.

The best practical choice is not to replace one white colourant with another, but to reduce reliance on foods where appearance matters more than nutritional value. Real food does not need titanium dioxide to be useful: meat, fish, eggs, vegetables, leafy greens, natural fats, fermented foods and simple sauces are judged by composition and satiety, not artificial whiteness.