An inorganic chemical, titanium dioxide is used as a dye to help products achieve a certain appearance, including whitening a product. Some experts and publications have described it as being akin to a paint primer that's used before the color is added to food in order to give products a uniform shine. Its presence is common in many items beyond Skittles including coffee creamers, cake mixes, and chewing gum. It's also used for pigment and in cosmetics manufacturing.

That came after a 2021 report from an expert panel at the European Food Safety Authority, which reviewed data on titanium dioxide safety. The panel said it couldn’t rule out concerns that the food additive might be able to damage DNA and possibly lead to cancer. They explained that after you eat something that has titanium dioxide in it, your body absorbs low levels of its particles – but the particles can build up as you eat more foods with this additive.