Red Dye No. 3, also known as erythrosine or FD&C Red No. 3, is a synthetic food coloring derived from petroleum that gives foods and drinks a bright, cherry-red color. It is used in many packaged foods, including candies, cakes, and other foods, as well as in some medications and supplements, such as cough syrup and gummy vitamins. The FDA banned the use of Red Dye No. 3 in cosmetics and externally applied drugs in 1990, based on a study that it can cause cancer in rats. However, the FDA still allows its use in foods, despite multiple studies linking consumption of synthetic dyes to behavioral issues in children, including hyperactivity. Red Dye No. 3 is a known carcinogen that’s used freely in the US food supply. California plans to ban Red Dye No. 3s usage in food starting in 2027, following a bill signed into law in October 2023.