Canthaxanthin is a cartenoid, which is a class of yellow to red pigments. Canthaxanthin colors brine shrimp and other crustaceans, as well as many fish, plants and mushrooms. Food manufacturers use canthaxanthin, also known as Food Orange 8, carophyll red or roxanthin red 10, as a color additive in certain foods, including barbecue and tomato sauces, soups, salad dressings, fruit drinks, candies and cheeses. In fact, most red, orange or yellow processed foods list canthaxanthin as an ingredient [FDA].
Tanning pills work because canthaxanthin easily dissolves in lipids, which make up the fatty layer directly under the epidermis. The canthaxanthin molecules attach to this layer of fat cells directly under the skin, giving the epidermis a brownish orange color [source: Drugs].
While a chemical that colors your skin in the same manner as carrots may seem safe, read on before you begin popping tanning pills.