In food products, E171 is not a singular ingredient; it’s always combined with other ingredients (e.g., proteins and fats) in the food product. Digesting food is a slow process for the body compared to drinking a beverage, which passes much faster through the body. 

The Colour of Barium Sulphate and Its Suppliers

Zinc Oxide

Until relevant toxicological and human exposure data that would enable reliable risk assessment are obtained, TiO₂ nanoparticles should be used with great care.