Impaired skin barrier in seborrheic dermatitis

One theory why seborrheic dermatitis occurs is that Malassezia yeast penetrates the outermost layer of our skin, the stratum corneum. This leads to inflammation, leading to more damage to the skin barrier, enabling Malassezia to burrow deeper in. You can picture the vicious cycle of inflammation and skin damage that ensues.

Repairing and maintaining a healthy skin barrier may be one of the best ways to prevent seborrheic dermatitis and maybe even cure it. You can do this by a multi-pronged approach of topical creams, diet and lifestyle changes. 

Check out my video on how repairing and maintaining your skin barrier can prevent and maybe even cure seb derm:

If you prefer to read, let’s take a deep dive:

What is the skin barrier?

The skin barrier is a term used to describe the combination of the outermost layer of skin, the stratum corneum (SC), and the acid mantle that overlays it. This layer of skin is essential for a number of reasons, including protecting the body from bacteria, pollutants and chemicals. It also helps to keep moisture in, which is why it’s so important to protect this layer when caring for your skin.

The stratum corneum consists of 10 to 30 thin layers of dead skin cells that have been shed from the surface of the epidermis (the layer under SC). The role of these cells is to act as a shield against environmental irritants.

The acid mantle is a thin film that covers the surface of skin. It’s made up of sebum (oil), sweat, and water. Its pH level falls between 4 and 6.5. This acidic environment helps to kill bacteria and prevents them from proliferating on the surface of your skin.

Sebum and sweat are crucial in forming the skin barrier. They work together to create a protective film that keeps out unwanted bacteria, pollutants and chemicals.

Both the stratum corneum and acid mantle work together to create a barrier that helps to keep moisture in and irritants out. It’s a system that works beautifully to protect us but it can get damaged so easily.

What damages the skin barrier?

Almost anything and everything can damage the skin barrier, including:

• Too much sun
• Excessive wind exposure
• Cold weather
• Chemicals (including soaps and detergents)
• Over-enthusiastic exfoliation (check out how your hygiene practices affect seb derm)
• Using alkaline products like baking soda
• Steroids!!
• Stress
• Sleep deprivation
• Contact with allergens or irritants (such as poison ivy)
• Skin infections
• High consumption of sugar
• Hot water

In other words, almost any internal or external stressor can damage or at least weaken your skin barrier, increasing your risk of Malassezia digging their figurative heels into your skin.

Relationship between an impaired skin barrier and seborrheic dermatitis

People with seborrheic dermatitis often have an impaired skin barrier function. This means that our skin is not able to protect us from the environment as well as it should be. As a result, our skin can become inflamed and irritated more easily. The tactful way of saying this is:

“We have sensitive skin.”

It’s code for – our skin barrier is not working and isn’t doing its job.

We don’t know which came first – impaired skin barrier or Malassezia – in the seborrheic dermatitis continuum. However, we know Malassezia is present on the surface of normal skin and is found everywhere on everyone. Numbers of surface Malassezia is not higher in SD sufferers but Malassezia levels in the stratum corneum is notably higher on skin affected by seborrheic dermatitis.

Some researchers proposed that a defective skin barrier is the root cause of SD. Once these changes occur, it encourages Malassezia growth and penetration, causing inflammation which further damages the walls of defence.

Further reading: Is seborrheic dermatitis a fungus?

Does seborrheic dermatitis damage the skin barrier?

There is evidence that seborrheic dermatitis damages the skin barrier. This complicated process happens through multiple pathways due to Malassezia and our own body’s approach to fighting it.

When our immune system detects the presence of Malassezia and its byproducts in our stratum corneum, it sends out a signal that says ‘Alert! Invaders!’ This leads to a ‘marching of the guards’. Immune cells gather and wage a war of inflammation, inadvertly breaking down the skin barrier further.

Malassezia itself, changes our sebum composition by ingesting triglycerides and other saturated fatty acids, leaving behind unsaturated fatty acids like oleic acid and arachidonic acid, which can be irritating, causing more inflammation. The change in sebum composition also changes our skin acid mantle.

How do we repair the skin barrier?

Prevention is always better (and easier) than cure. Protect your skin from elements that will damage it. Most of it is common sense. Wear sunscreen, a hat, and protective clothing to help shield your skin from the sun.

Use a good moisturizer after bathing to help retain moisture in your skin. Avoid harsh chemicals and contact with allergens and irritants. Stripping your skin of it’s natural inhabitants can cause an imbalance in your skin microbiome which ultimately leads to aggravation of Seb Derm. 

However, once your skin is damaged, you’ll need to give it more TLC. And remember, healing takes time. Our body is pretty good at healing itself, but you need to get out of its way.

Even if you have seborrheic dermatitis, the basic principles of repairing and maintaining your skin barrier is the same as anyone else’s. However, you need to be a bit more careful with the types of creams you put on your skin. I’ll go into more detail below.

Topical creams to repair skin barrier

The creams that you choose to put on your skin only need to do two things:

• protect your skin from the environment
• provide ingredients needed to replenish your skin barrier

Any cream, oil, toner, serum, lotion or potion that doesn’t do one or the other goes in the bin. A collagen gel that I use is Dr Lewinn’s Ultra R4 Collagen Plumping Gel (read my review).

Your cream also needs to avoid doing one thing:

• damage your skin barrier further by irritating it or breaking it down

If you are concerned that a cream is irritating your skin, regardless of how many 5-star reviews it has and how many lofty promises it makes, leave it off.

This doesn’t leave very much on the list does it?

In general, choose a gentle moisturizer that contains ingredients like ceramide, niacimide, vitamin E and hyaluronic acid. Avoid ones with retinol, synthetic fragrances, and petrolatum.

Check it out on Amazon

Further reading: The 6 Best Face Moisturizers For Seborrheic Dermatitis

Even though most expert advice includes an emollient, e.g a glycerin-based or petrolatum-based moisturizer, be careful. Theoretically, it makes sense to reduce loss of moisture. However, because these moisturizers are heavier, and often leave a slightly waxy film of protection on your face, it can sometimes clog pores, increase sebum production and make your face oilier, aggravating seborrheic dermatitis and damaging the skin barrier further.

Your skin is naturally acidic for good reason. The products that you use should match the pH of your skin so it doesn’t disrupt this fine balance. There is no cheap way to test the pH of your face at home but you can easily test the pH of your skin care products and make sure they are acidic. Find pH strips in most chemists or on Amazon:

Check it out on Amazon

Another common advice is to use plant oils as there is some evidence that these oils may help repair the skin barrier. I agree that plant oils have many beneficial effects. However, SD skin is often already on the oilier side and don’t need additional oils clogging our pores. Also, many plant oils contain oleic acid, which we are hyper-sensitive to. The introduction of more oleic acid to our skin will trigger more inflammation and scaling instead of promoting repair.

Check out Seborrheic dermatitis: common oils to avoid for a deep dive.

Even though you will never see antifungal cream listed in any ‘how to repair your skin barrier’ article, I insist that you have an antifungal cream in your arsenal at all times. As explained before, Malassezia damages your skin barrier. To  break the vicious cycle of inflammation and skin damage, we need to kill those buggers. Applying an antifungal cream twice daily does wonders to reduce the Malassezia load on your skin. This allows your skin to start rebuilding its defenses again.

Further reading: What is the best antifungal cream for seborrheic dermatitis?

Diet changes to repair your skin barrier

Even though so much attention is given to creams, the most important thing you can do for your skin health is to have a healthy diet.

Some good dietary changes to make include reducing your intake of sugar and processed foods, and eating more whole fruits and vegetables. You should also try to drink plenty of water each day, as dehydration can also contribute to impaired skin barrier function.

Another thing that you can do is introduce probiotics into your diet. Probiotics are beneficial bacteria that help keep the gut healthy and may also help improve skin health. You can find probiotic supplements at most pharmacies or health food stores.

Check it out on Amazon

Consuming yogurt or kefir regularly also helps improve your skin barrier and reduce redness.

Making these dietary changes will not only help improve your skin barrier function, but they will also benefit your overall health.

Lifestyle changes to repair skin barrier

The way you live your days if the way you live your life – Annie Dillard

If you’ve had a rough life, it shows on your skin. I don’t mean you need to pamper your body all the time but there are some important things you can do to improve your skin health.

The main ones are to stop smoking (if you are a smoker), and to start exercising. Maintain good hygiene. And stay away from pollution. Learn skills to deal with stress and depression, and start meditating.

To wrap up

Maintaining a healthy, functioning skin barrier may be your answer to preventing (and maybe even curing) seborrheic dermatitis flares. Plus, having healthy, strong skin is an amazing confidence-booster! You have all to gain and nothing to lose by taking care of your skin properly.