Most of us have our skincare routines down to a science–a gentle cleanser, a trusty vitamin C serum, maybe a bit of exfoliation or retinol in the evenings, and the ultimate non-negotiable: SPF. You might even throw in some collagen-boosting peptides and niacinamide for good measure. But when colder weather sets in (and boy, has it set in) our skin may require a little extra TLC.

Enter ectoin, a molecule that protects stressed-out skin while locking in moisture. Naturally found in organisms that live in extremely harsh conditions (think high salinity water and arid environments), ectoin protects these organisms and allows them to thrive in less-than-ideal conditions.

McKenzie Bolt, global education director at Biossance, likens the molecule to a “water magnet”. “Ectoin draws moisture into the skin and then as a bodyguard, creating this protective wall of moisture around the skin,” she says. When our skin is exposed to less-than-ideal conditions, ectoin steps in as the first line of defense, keeping the skin barrier happy. That’s why the brand chose to include it in its latest launch, the Squalane + Ectoin Overnight Rescue. We headed to NYC to chat with Bolt about the role of Ectoin in skincare and why–when combined with a few other heavy-hitting ingredients–it can be a serious game changer when it comes to your nighttime skin routine.

Biossance Squalane + Ectoin Overnight Rescue, $92


It starts with the skin barrier

We can talk about the skin barrier all day long, but for the TL;DR crowd, a good way to think of your skin barrier is to imagine a flat jenga puzzle. “When we experience a weakened skin barrier, it’s like a piece of the Jenga is missing from the puzzle,” says Bolt. The “missing pieces” represent dryness, rough patches, redness and irritation in the skin. This can be triggered by a multitude of factors: when the environment sucks hydration from your skin, the stress of pollution, UV radiation and lack of sleep, for example. But it also can just happen when we overuse acids or retinols. The trick, says Bolt, is to counteract stronger formulas with products that soothe and repair the skin.

How does ectoin help to balance the skin?

Active ingredients like retinol and acids are fantastic for increasing cellular turnover, but too much of a good thing can disrupt the skin barrier. Ectoin does all the repair work. “It hydrates, [tones] down inflammation, redness and irritation,” says Bolt. Unlike its counterpart, hyaluronic acid, ectoin doesn’t need to be paired with additional ingredients to retain moisture. Plus, ectoin doesn’t interact or disrupt the effectiveness of other skincare ingredients, it’s an ideal “buffer,” complementing other serums or active components in your routine.

Why use ectoin for nighttime skincare?

Ectoin works its magic around the clock, but evenings are prime time since the skin naturally repairs itself when it’s in a state of rest. “When we sleep, our heart rate goes down, everything turns inward, our blood flow goes up,” sals Bolt. Biossance Squalane + Ectoin Overnight Rescue incorporates magnesium and peptides to the mix to take those restorative qualities to the next level. “Ingredients that [can] inhibit neurotransmitters that stress us out can also do wonders for your skin,” she says. While peptides smooth and soften the complexion, topical magnesium encourages cellular regeneration for an overall brighter appearance.

Who can benefit from ectoin?

Ectoin isn’t picky. Whether you’ve faced harsh winds on a ski trip, endured jet lag, or are a new parent navigating sleepless nights, ectoin is a worthy addition to your skincare lineup. “What we’re doing [with our new product] is taking that ectoin to where it needs to be, preventing transepidermal water loss and being your skin’s bodyguard against the stress it’s obviously gonna face,” says Bolt. “Think of ectoin as the crock pot of skincare–set it and forget it.”