Consumers are surrounded with candies and processed foods containing synthetic food dyes. Increasingly, these dyes have been found to increase hyperactivity and other disturbed behavior in children. These synthetic dyes, mostly petroleum-derived, are unnecessary. While synthetic dyes are especially common in foods marketed to children, they are also used in in a number of foods such as some cereals, butter, the skin of fruit and the casing of hotdogs. This smart guide for parents describes why synthetic food dyes are used, associated children's health concerns and what can be done.