FD&C dyes are approved by the FDA and stand for Food, Drug and Cosmetics. As of now there are only seven dyes that have been approved by the F.D.A. for safe use in food, drugs and cosmetics. These are known as the FD&C dyes. These dyes are yellows #5 and #6, reds #3 and #40, blues #1 and #2, and green #3. The most popular of these dyes is Red #40. The second most popular is Yellow #5.