Titanium dioxide that's found in icing has been linked to inflammatory bowel diseases
"Titanium dioxide—an additive that's used to make white appear even whiter—can be found in a variety of foods, like coffee creamer, icing, powdered sugar, and ranch dressing. However, for the exact same reason, it is used in making sunscreens, laundry detergents, and paint. FDA considers the additive safe; however, there was research conducted that linked it to inflammatory bowel diseases. In addition to this, as of 2020, France has banned titanium dioxide in food."