Skin Science

What's a Skin Barrier?

Diving deep into your acid mantle.

Meghan Maupin, CEO

CEO of Atolla

Meghan Maupin, CEO

Meg is the CEO and Co-founder of Atolla. She has a graduate degree in Engineering and Management from MIT, and previously worked in design roles at Patagonia, The MIT Design Lab, and Formlabs.



We talk a lot about the skin barrier and pH at Atolla, and for good reason: it's the first line of defense when it comes to protecting your skin from all the pollutants out there, which means a strong skin barrier can be crucial to maintaining healthy skin. Here's what exactly it is and what to do if yours is damaged.

What is a skin barrier?

The stratum corneum is the outermost layer of our skin and contains our acid mantle, which is a vital part of our "skin barrier.” This barrier protects our skin from bacteria, pollutants, and irritants. Not only does it help keep the bad stuff out, it's also what helps keep moisture in by preventing transepidermal water loss. 

How do I know if my skin barrier is damaged?

A properly functioning skin barrier is key to healthy skin. When your skin barrier is damaged, there are tiny cracks in the barrier that allow moisture to get out and irritants to get in. You can tell this a few different ways: 

  • Tight, red, irritated skin 
  • Stinging when you apply products
  • pH that’s out of balance  

The skin barrier is naturally acidic, around 5.5 pH, which is key in its function to neutralize pathogens. If you’re an Atolla member, you can measure the pH of your skin and see if it’s in a healthy range using our at-home Skin Test (learn more about the Skin Test here). 

What should I do if my skin barrier is damaged?

  1. Detox: Your skin is great at regulating itself, so in the case of irritation, it's best to give your skin a break and let it get back to normal. Use the basics, no actives, and don’t add any new products. 
  2. Pause any new products: Try to reduce further irritation by cutting back any recent additions to your skincare routine.
  3. Simplify your routine: Often the skin barrier gets damaged by over-exfoliating. Less is more, and a good routine only needs to be 3-4 steps to see great results without risking ingredient conflicts.
  4. Look at pH: The pH of products like soap can be very high, and when used on unbalanced skin can wreak havoc. It's best to use products with pH close to your skin's healthy pH range of 4.5-6.
  5. Add healing ingredients: Ingredients like glycerin, ceramides, panthenol and fatty acids can help heal and repair your skin barrier.
  6. Always use sunscreen: This should already be part of your daily routine, but sunscreen is key to protecting your skin barrier from further damage by the sun.

Simplify your skincare with a custom, complementary routine.