Food coloring is an ingredient that can be added to food or other items to enhance or add color. Food coloring can be homemade or commercially produced, naturally derived, or made from synthetic materials. All food coloring is edible, though some people may have sensitivity to food coloring. A food color additive extracted from dried bugs and commonly used in fruit drinks, candy, yogurt and other foods can cause life-threatening allergic reactions. It can also cause palpitations, hives and itching in children, restlessness, sleep disturbances and asthma.