Sensitive Skin: Beyond the Skin Barrier

May 15, 2023

What sensitive skin teaches one about skin intelligence

As a complete ecosystem, the skin plays host to diverse microorganisms collectively known as the microbiome. Barrier function is a critical component of skin health that ensures the survival of good germs, effective cell communication and self-regulation. Healthy skin barrier function in turn requires ceramides which are key constituents of the skin barrier and which we explore in this article.

@drteowanlin Ceramides: What You Must Know… to dermatologists ceramide moisturisers are the holy grail of skincare. Expensive ceramide moisturisers are well-known, but what many don't realise is that healthy skin is fully capable of producing its own ceramide ! That doesn't mean you skip your ceramide moisturiser though…for more bite-sized skincare tips, get my newsletter👆🏻 #skincare101 #skincaretips #sensitiveskincare #skincarehacks #skincareroutine #ceramides #ceramideskincare #singaporedoctor #singaporedoctors #skincare #dryskin #dehydratedskin #moisturizer #ceramidemoisturizer #dermatology #dermatologist #dermdoctor #learningisfun #learnontiktok ♬ original sound – Dermatologist Dr.TWL

Sensitive skin isn’t really all that allergic, it all boils down to an impaired skin barrier

Decades ago, atopic dermatitis was interpreted as a predominantly allergic type skin condition—it’s true. Sufferers tend to be allergic to house dust mite, pollen and VOCs. They also have associated conditions under the umbrella term of the “atopic triad”—asthma, allergic rhinitis/hay fever.

Then, studies emerged which showed that eczema was really due to a deficiency in filaggrin gene expression—a fact already established in conditions such as icthyosis vulgaris. This led to impaired ceramide production, which meant that the epidermis became “leaky”. Out of this emerged the brick and mortar model of the skin barrier— the bricks are superficial skin cells known as corneocytes, and the fatty lipids which join the corneocytes together, the cement. This lipids known as ceramides could be replenished with ceramide-dominant moisturisers which fill the “gaps” between the bricks.

When sensitive skin is treated with barrier repairing moisturisers, it becomes less reactive to environmental triggers.

The Art of Replacing Like for Like

Ceramide Skincare Harnessing Skin Intelligence

Over 340 types of ceramides exist within the human stratum corneum alone. The composition of which is varied. From the 12 classes identified researchers conclude the following:

The basic ceramide structure is composed of:

Sphingoid base joined to a fatty acid via an amide bond

@drteowanlin Ceramide benefits in moisturizer for dry skin Improve skin hydration Reduce water loss from skin Increase skin’s natural ceramides Anti-inflammatory Beneficial for those with eczema, or atopic dermatitis Most ceramides beauty brands refer to are synthetic or animal sources, i.e. bovine in origin—which is also a concern for those preferring a vegan lifestyle. Dermatologist Dr. Teo Wan Lin’s top pick for ceramides is a lesser-known subtype known as phytoceramides. These are botanically derived from plant seed oils and the most prominent phytoceramide of all is shea butter. Derived from the shea tree, shea butter provides a rich source of natural origin plant-based ceramides that can repair the skin barrier effectively. Benefits of phytoceramide skincare Enhance hydration better than synthetic ceramide Improve the recovery rate of damaged stratum corneum Improved immunity Anti-inflammatory #dryskin #moisturiser_for_dryskin #moisturisertreatment #sgskincare #dermatologytiktok #sgtoktok #sgdoctor #dermatologist #tiktoksg🇸🇬 #skincareroutine #skincaretips #skincare101 #skincareproduct ♬ original sound – Dr.TWL Dermatologist

Skin, your ceramide factory:

7 Stages of Ceramide Synthesis

Stratum basale stage

Beginning at the bottom most layer of the epidermis, the stratum basale
Ceramides are made within the endoplasmic reticulum

Golgi apparatus: sphingomyelin

Converted to sphingomyelin in the Golgi apparatus

Secretory vesicles

Packed into secretory vesicles (bubble-like)

Multiply & differentiate

These vesicles multiply as skin cells (keratinocytes) differentiate and move towards the surface of skin

Release

The bubbles burst and release sphingomyelins

Ceramide conversion

Sphingomyelins converted back to ceramides

Compaction

Packed into secretory vesicles (bubble-like)
These vesicles multiply as skin cells (keratinocytes) differentiate and move towards the surface of skin
The bubbles burst and release sphingomyelins
Sphingomyelins converted back to ceramides
Ceramides, free fatty acids & cholesterol are compacted into layers in the stratum corneum to form the skin barrier

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