Food additives used to preserve flavor or to enhance the taste and appearance of foods are also available in oral hygiene products. The aim of this review is to provide information concerning food additives in oral hygiene products and their adverse effects. A great many of food additives in oral hygiene products are potential allergens and they may lead to allergic reactions such as urticaria, contact dermatitis, rhinitis, and angioedema. Dental practitioners, as well as health care providers, must be aware of the possibility of allergic reactions due to food additives in oral hygiene products. Proper dosage levels, delivery vehicles, frequency, potential benefits, and adverse effects of oral health products should be explained completely to the patients. There is a necessity to raise the awareness among dental professionals on this subject and to develop a data gathering system for possible adverse reactions.