DMDM hydantoin is a preservative in cosmetics and personal care products. It works by slowing and preventing spoilage in products such as shampoos and hair conditioners, and in skin care products like moisturizers and makeup foundations.

What is DMDM hydantoin and why is it bad?

DMDM hydantoin is a preservative and antimicrobial agent found in a wide range of cosmetics and skin-care and hair-care products. It's considered a “formaldehyde donor.” That means it releases a small amount of formaldehyde over time to help keep products fresh and free from contaminants.

Why is DMDM hydantoin bad?

The alleged culprit for the hair loss is DMDM hydantoin, a formaldehyde-releasing preservative, which has since been under scrutiny by the beauty community. ... It continues, “formaldehyde is a well-known human carcinogen that can cause cancer and other harmful reactions when absorbed into skin”.