Calcium carbonate and titanium dioxide are two important minerals that are widely used in various industries. While they share some similarities, they also have distinct differences when it comes to their manufacturing processes and applications.

Even if you’re not familiar with titanium dioxide in makeup, it’s quite likely you’ve seen it in sunscreens, specifically physical formulas. Titanium dioxide is beloved in cosmetics not only for the pigment and coloration it can provide but also for the way it reacts to light.

“Unlike some other chemicals used in food, titanium dioxide has no nutritive, preservative, or food safety function—its use is purely cosmetic,” said CSPI principal scientist for additives and supplements, Thomas Galligan. “The prospect of titanium dioxide nanoparticles damaging DNA is concerning enough for us to recommend consumers avoid foods that have it.”