Diazolidinyl Urea

Up next in Living Well Mama is another one of those Red Flag ingredients that you’ll NEVER find in Crunchi, and something to be on the lookout for in your makeup, personal care, and even (gasp) your FOOD!


In your food, its used to make baked goods brown, like pretzels and bread. 


Diazolidinyl Urea is an antimicrobial preservative that works by forming formaldehyde in cosmetic products. Urea in cosmetics, is man-made in the laboratory and the raw materials are ammonia and carbon dioxide. Not something you’d think you’d put on your skin, right?


According to a study published in 2010, ureas can release formaldehyde, which has been classified as a human carcinogen. According to the Material Safety Data Sheet on this substance, urea can cause skin and eye irritation, and prolonged exposure can cause reproductive effects. 

Whether related to its tendency to release formaldehyde or not, urea has a tendency to cause allergic reactions. Those with sensitive and infected skin are advised to steer clear of this ingredient. In fact, the American Academy of Dermatology has established diazolidinyl urea as a primary cause of contact dermatitis.


In the U.S. approximately 20% of cosmetics and personal care products contain a formaldehyde-releaser and the frequency of contact allergy to these ingredients is much higher among Americans compared to studies in Europe, where these ingredients are banned.


Often found in: Facial moisturizers, facial cleansers, anti-aging creams, body lotions, eye creams, foundations, shampoos & conditioners, bubble bath, baby wipes, styling mousses and foams, acne treatments, lip balm/treatments, mascara, sunless tanning products, antiperspirants/deodorants, nail polishes


Also under the names: Diazolidinyl urea, Imidazolidinyl urea, DMDM hydantoin, Sodium hyroxymethylglycinate