Ectoin is a small, amino acid-derived molecule known as an extremolyte, which is found in microorganisms that thrive in extreme, harsh environments. Said to have been first discovered in a salt lake in Egypt’s Wadi El Naturn desert, where the built-in self-defense molecules helped guard microorganisms against salt-induced dehydration, ectoin can be naturally and chemically derived. It helps to improve hydration and smooth skin while shielding it from pollution and sun damage caused by UVA rays. “Ectoin is like a superhero for your skin,” says Mary Berry, cosmetic chemist, CEO, and founder of Cosmos Labs. She adds that it’s particularly good for alleviating dryness and sunburn aftermath. “Plus, it’s gentle enough for sensitive skin, making it a must-have in your daily skincare routine.”