If you’ve ever worried over a cholesterol reading, struggled with excessively oily skin, or taken hormonal therapies to balance estrogen or testosterone levels, then you’ve experienced first-hand the diverse roles lipids play in the body. 

Along with proteins, carbohydrates, and nucleic acids, lipids are one of the four so-called “molecules of life;” all life on earth is built from these molecules. Of these four groups of molecules, lipids are some of the most difficult to classify and define; some biologists argue that lipids encompass a greater array of structural variation than other large biological molecules.

Lipids are essential to life in each of the five biological kingdoms. They are so critical to survival that many researchers believe they are the key to understanding the origins of life. Energy storage, metabolism, the production of hormones, and intercellular signaling are just a few of the complex tasks carried out by lipids in our bodies–but do they figure into skincare or eczema management at all? 

In a word, yes. Lipids play a critical role in both the structure and the function of the skin barrier, our immune system’s first shield against noxious substances and pathogens in the environment. 

 What are lipids?

Lipids are a group of organic compounds with a fatty, oily, or waxy consistency. All lipid molecules are constructed of hydrogen, oxygen, and carbon atoms; while some lipid molecules also include phosphorus and other atoms, oxygen, carbon, and hydrogen are required for a lipid molecule to form. 

Most lipid molecules are nonpolar, meaning that the molecule has no electrical charge; a few have a weak electrical charge and are only slightly polar. Lipids cannot be dissolved in polar molecules such as water; you’ve seen this trait at work if you’ve ever shaken a bottle of vinaigrette or washed a greasy pan. Only nonpolar compounds such as acetone or benzene can dissolve lipids. . 

Oily lipids include plant oils such as olive oil, while butter, lard, and tallow are fatty. Beeswax, ambergris, and carnauba wax–which comes from the leaves of the carnauba palm—are examples of waxy lipids. 

B. Different types

Lipids are notoriously challenging to classify. Scientists have been debating the classification system for lipids for over 100 years. For our purposes, we’ll discuss the types of lipids relevant to the skin’s structure and function. These include: 

• Fatty acids, both saturated and unsaturated
• Glycerides, which contain glycerol
• Sphingolipids
• Steroids
• Waxes

Fatty acids 

Fatty acids are formed of a carbon atom double bonded with an oxygen atom and single-bonded with a hydroxyl group (one oxygen atom bonded to one hydrogen atom). Almost all lipids contain fatty acids; steroids are the exception. 

Fatty acids are abundant in nature, with over 70 currently identified. They can be subdivided into saturated fatty acids and unsaturated fatty acids. 

Saturated Fatty Acids

Saturated fatty acids contain no carbon-to-carbon double bonds and are “saturated” with hydrogen atoms. Their molecules are packed tightly into a net-like structure, which allows them to remain solid at room temperature and to have relatively high melting points–the same is true of the fats made from these fatty acids. Saturated fats are nonpolar and strongly hydrophobic, meaning they repel water. 

Saturated fatty acids are found in mammal fat (such as lard and tallow), butter, and coconut oil. 

Saturated fats are thought to be pivotal to maintaining the integrity of cellular membranes. Studies also suggest that they are integral to protein-signaling and wound-healing. 

Unsaturated Fatty Acids

Unsaturated fatty acids can be mono- or polyunsaturated. Monounsaturated fatty acid molecules contain a single carbon-to-carbon bond. Polyunsaturated fatty acid molecules contain two or more carbon-to-carbon double bonds. 

Unsaturated fatty acids are not solid at room temperature, owing to the lack of hydrogen saturation, and many of them are slightly polar–meaning that they are less hydrophobic than saturated fats.

Essential fatty acids are needed for normal cellular function, but they are not produced by the human body. This means that it is necessary (“essential”) to obtain them through diet. Only two fatty acids–the polyunsaturated fatty acids linoleic acid, an omega-6 fatty acid, and α-linolenic acid (ALA), an omega-3 fatty acid–are known to be essential to humans.

Our cells rely upon omega-6 and omega-3 fatty acids as a source of energy. They are also vital parts of the cellular membrane. They maintain cellular structure and preserve their function. They are required for the metabolism of cholesterol and are precursors to several key micronutrients. They are also essential for the synthesis of eicosanoids, which are a bountiful group of lipid-based signaling molecules that help regulate innate immune responses. 

Prostaglandins, which are produced by all mammalian cells, are an eicosanoid, as are leukotrienes. These molecules are part of the innate immune system’s rapid response to bacteria, and they kick off some of the most notable signs of inflammation–redness, swelling, and pain. 

Some eicosanoids act to curtail inflammation once pathogens have been expelled. Diets rich in omega-3 and omega-6 polyunsaturated fatty acids are associated with lowered levels of inflammation and overall balancing of the immune system. 

Glycerides

Glycerides are fatty-acid esters, produced by the bonding of a fatty acid to an alcohol called glycerol. You may be at least passingly familiar with triglycerides: they are the product of a bond between glycol and three fatty acids. 

Fatty acids comprise about 94 to 96 percent of the total weight of glyceride molecules. Fatty acids also make up the reactive part of a glyceride molecule; for these reasons, the physical and chemical properties of any particular glyceride depend upon the fatty acids that make it up. 

This in no way suggests that the glycerol in these molecules is unimportant. As we’ll discuss later, the skin needs glycerol. It accelerates the healing of injured tissues and also appears to have an antimicrobial effect. As glycerides are broken down in different body systems, glycerol is released along with the fatty acids to assist with these functions. 

Sphingolipids

Sphingolipids are critical to the regulation of cellular signaling pathways, the complex channels through which cells communicate with each other; these pathways allow cells to elicit responses from cells such as immune system cells. By facilitating and regulating these pathways,  sphingolipids are a dynamic part of maintaining homeostasis. 

As a class, sphingolipids encompass a large and varied group of lipids, each with its own distinct structure and function. Sphingolipids are found abundantly in the membrane bilayers–a double layer of lipid molecules in which membrane proteins are suspended. If membrane lipids are placed in water, they compartmentalize and seal themselves off. The fluid movement of sphingolipids allows them to reseal these compartments quickly if they’re torn or otherwise breach.

Unlike most lipids, sphingolipid molecules are amphipathic–this means that they have both hydrophobic and hydrophilic (attracted to water) ends. They are moderately water soluble. 

Sphingolipids are necessary for the organization of extracellular spaces (such as the skin barrier). They are associated with cellular growth and cellular differentiation (such as the differentiation of keratinocytes), controlled cell death (called apoptosis), and chemotaxis, the process by which cells can move in response to stimuli. An example would be an immune system cell migrating towards injured tissues or invading pathogens. 

Ceramides are a type of sphingolipid. They comprise about 50% of the skin barrier’s lipid content. 

Steroids

Steroids are unique among lipids. Like all lipids, they comprise one each of hydrogen, carbon, and oxygen atoms, and they are not water soluble. Their structure, though, is quite different, consisting of 17 carbon atoms arranged in four fused hydrocarbon rings, and they do not have fatty acid chains.

Steroids are a diverse group that includes bile salts, the sex hormones (estrogen and testosterone, for example), cholesterol, and adrenal cortical hormones (such as cortisol). These examples underscore the wide variety of functions played by steroids, each determined by the unique chemical structure of the steroid at work.  

Steroids are important to metabolism, energy storage, reproduction, and modulation of inflammation. Studies suggest that sex hormones and glucocorticoids play a role in the cellular processes of the central nervous system, influencing both neurodevelopment and neurodegeneration. 

Cholesterol is a hydrophobic steroid found in all cellular membranes. It plays a fundamental role in  the synthesis of sex hormones and vitamin D. It is an important part of the skin barrier, where it helps to repel water and prevent moisture loss from the epidermis. 

Waxes

The phrase “like water off a duck’s back” owes itself to waxes. Like glycerides, waxes are esters; they are formed from the bonding of long-chain fatty acids with long-chain alcohols. They can be found on the surfaces of leaves (especially those in rainy, tropical biomes), fruits, stems and flowers, where they help prevent dehydration of plants and repel pathogenic microorganisms. Waxes can also be found in the skin of animals, where it keeps feathers and hair soft and water-resistant–which is why water can roll off a duck’s back. 

In the human body, the meibomian glands of the upper and lower eyelids produce and secrete an oily lubricant that combines with tears to help the eyes maintain their moisture. While the substance produced by the meibomian glands is not a wax in and of itself, it does contain wax esters. 

Wax esters can also be found in sebum, the so-called “oil” that lubricates the hair follicle (and sometimes contributes to the development of acne. Sebum gets an unfair reputation, due to the pimples sometimes attributed to “oily” skin. However, it provides many benefits to the skin; it protects the hair follicle from friction and helps it repel moisture. It has anti-inflammatory properties, transporting antioxidants to the skin and offering a degree of protection from ultraviolet light. 

Sebum also has antibacterial properties, and it appears to be part of the skin’s defense against staphylococcus A.

 

Lipids and the skin

From what you’ve read so far, you may have deduced that lipids have a multitude of important functions in the skin. Lipids are found in every layer of the skin, and they play many different roles. As in other body systems, lipids play an essential role in maintaining homeostasis, helping the skin to adjust to external changes so that it can continue to function normally. 

Where are lipids found in the skin? 

Lipids are found throughout the skin, from the hypodermis (the skin’s deepest layer) to the epidermis (the skin’s outermost layer). Each layer of the skin has a distinct lipid composition. 

The Hypodermis

The hypodermis is the deepest layer of your skin. It serves as a buffer between your dermis and your muscles and bones. It is made up of connective tissue as well as adipose tissue–the “fat” that many people try to keep at bay through diet and exercise. It acts to insulate the body against temperature changes, and it supports the dermis. The hypodermis also stores fat as a source of energy. 

The Dermis

The dermis is composed mostly of connective tissue. It is the layer of skin where blood vessels, sweat glands, hair follicles, and sebaceous glands are found. The sebaceous glands, as we discussed earlier, produce sebum, a complex, oily/waxy compound that lubricates the hair follicle. 

Sebum is composed of squalene, glycerides, wax esters, fatty acids and cholesterol. The predominant components of sebum are triglycerides and fatty acids, which together make up 57.5% of its total lipid content. Wax esters are the second-most predominant lipid, accounting for 26% of sebum’s total lipid content, followed by squalene (12%). Cholesterol is the least abundant lipid in sebum, accounting for only  4.5% of total lipids. 

Squalene and wax esters are distinctive to sebum. Squalene is not produced anywhere else in the body, and aside from the meibomian glands, neither are wax esters.

Sebum gets an unfair reputation due to its oily consistency–an attribute it owes to squalene. However, it provides many benefits to the skin; it protects the hair follicle from friction and helps it repel moisture. It has anti-inflammatory properties, transporting antioxidants to the skin and offering a degree of protection from ultraviolet light. It also combines with sweat and fatty acids to form the acid mantle–a feature of the epidermis we will discuss later. 

Sebum also has antibacterial properties, and it appears to be part of the skin’s defense against staphylococcus A. Animal studies also suggest that sebaceous secretions defend the skin against ultraviolet radiation, in addition to aiding thermoregulation. 

The Epidermis

Lipids are predominantly found in the epidermis, the outermost layer of skin The epidermis itself is made of four distinct layers. Epidermal lipids are most abundant in the stratum corneum, the outermost layer of skin, comprising up to 15% of its weight (proteins comprise about 80%). The stratum corneum is made of flattened, elongated corneocytes, which are keratinocytes that have lost their nuclei and organelles. 

Corneocytes consist of a tough, fibrous protein called keratin. Each is ensconced in a thin, dynamic layer of ultra long-chain ceramides or ultra long-chain fatty acids. This layer is known as the corneocyte lipid envelope, or CLE.  

They are organized into about 15-25 layers of cells arranged in brick-and-mortar pattern; lipids form the “mortar” in the spaces between the corneocytes, providing both cohesion of the corneocyte “bricks” and a water-resistant barrier. 

The lipid subclasses found in the stratum corneum consist primarily of  ceramides, cholesterol, 

and fatty acids.  

Dynamic Function of Lipids in the Skin

Lipids are integral to both the skin’s structure and function. Some knowledge of the epidermis and the process of keratinocyte differentiation are central to understanding  the roles they play. 

Keratinocyte Differentiation and Epidermal Lipid Synthesis. 

Lipid production in the epidermis is intimately tied to the production and differentiation of keratinocytes. Keratinocytes go through many changes as they progress to their final stage as corneocytes. The epidermis has four distinct layers, and keratinocytes change as they pass through each of them: 

• The stratum basale is bound to the dermis by the basal lamina or “basement membrane.” Keratinocytes are produced by stem cells in this layer. Some of these cells will remain in the stratum basale, where they will continue to generate new keratinocytes by dividing. Others will migrate upwards to undergo changes in the upper layers.
  
  
• In the stratum spinosum, or spiny layer, keratinocytes take on a “spiny” appearance. These “spines” are known as desmosomes, and they allow the keratinocytes to interlock like puzzle pieces.
  
  
• The stratum granulosum is where keratin production begins to accelerate. In this layer, the keratinocytes accumulate keratohyalin granules. Their nuclei begin to deteriorate. The “spiny” keratinocytes begin to flatten into interlocking quadrilaterals, and tough bundles of keratin become more noticeable..
  
  
• In the stratum corneum, the outermost layer of the skin, keratinocytes shed their nuclei and cytoplasmic organelles–thus becoming corneocytes. The flattened cells interlock in a brick-and-mortar pattern.. They will be shed, or desquamated, when new keratinocytes migrate up to take their place.  

Many important changes take place in the composition of lipids within the keratinocytes as they migrate. As they move into the upper layers of the stratum spinosum, they develop  organelles called lamellar bodies or lamellar granules that secrete fatty acids and enzymes. During the migration from the stratum spinosum to the stratum granulosum, the lamellar bodies are pushed from the center of the keratinocytes to the margins of the inside of the cell. 

The migration from the stratum granulosum to the stratum corneum represents the most dramatic change in lipids. At this stage, the phospholipids in the plasma membrane of the keratinocyte are broken down into glycerol, fatty  acid chains, and enzymes such as glucosylceramides. 

The products of phospholipid breakdown are used to form the ceramide molecules that are central to the skin’s barrier function. Additionally, as the keratinocyte sheds its nucleus, its lamellar bodies are ejected. Once ejected, the lipids and enzymes produced by the lamellar bodies are evacuated from the organelles and become part of the intercellular “mortar” between the corneocytes. 

Time for a breakdown: how filaggrin affects lipid content

Lipids are affected by changes to other molecules during differentiation, as well.  As keratinocytes prepare to migrate into the stratum granulosum, they begin to synthesize particles called  keratohyalin granules. Keratohyalin granule production increases as the keratinocytes move through the layers of the epidermis. Keratohyalin granules produce a protein called filaggrin. Filaggrin promotes the formation of keratin bundles as keratinocytes develop, a crucial part of their transformation into corneocytes. 

In the stratum corneum, the keratohyalin granules release all their contents, including filaggrIn. Combined with the lipids expelled by the lamellar bodies, it becomes a part of the intercellular spaces between corneocytes. 

Enzymes from the lamellar bodies break the filaggrin down into  amino acids such as urocanic acid, one of the skin’s major natural moisturizing factors. Urocanic acid also contributes to the formation of the skin’s acid mantle, a thin acidic film that serves to draw moisture into the stratum corneum. The acid mantle also helps maintain the skin’s normal pH.

What does any of this have to do with lipids? Without the products of filaggrin breakdown and a proper pH, the ceramides necessary to the skin’s barrier function cannot be synthesized. This leaves the skin vulnerable to dryness and invasion by irritants. 

Lipids and Eczema

By now, we’ve touched upon the major lipid classes in the skin. We’ve looked at the adipose tissue of the hypodermis, which provides structure and insulation to the skin. From there, we’ve visited the dermis, where sebaceous glands produce sebum, a combination of lipids that lubricates hair follicles, provides a measure of UV protection, and might even defend against staph infections, all while facilitating the formation of the epidermal acid mantle. 

We’ve seen how keratinocytes start out in the stratum basale as normal cells with a nucleus and a plasma layer rich in phospholipids (a subclass of sphingolipids). We learned about the synthesis of lamellar bodies In the stratum spinosum, and saw those same lamellar bodies shift to the peripheries of the cell as the keratinocytes move towards the stratum granulosum. We saw keratinocyte structure changing, going from the spiny cells found in the stratum spinosum becoming more flattened and diamond-shaped  in the stratum 

We ultimately arrived at the stratum corneum, where keratinocytes meet their destiny as corneocytes. They are now tough masses of keratin that have been molded and elongated, and they’re encased in the corneocyte lipid envelope full of long-chain fatty acids. 

They expel their lamellar bodies, which then expel the assortment of lipids and enzymes within them. The keratohyalin granules likewise exit the keratinocytes and spill their contents, which include filaggrin. All together, these lipids, enzymes, and proteins–along with a small amount of sebum–fill the spaces between the corneocytes and become part of the skin barrier. 

As it breaks down into its respective amino acids, the filaggrin molecules help sustain the skin’s acid barrier and stimulate the synthesis of ceramides. Phospholipids from within the lamellar bodies break down into smaller lipids. Ceramides, one of the products of phospholipid breakdown, become dynamic actors in the function of the skin. Cholesterol and ceramides are essential precursors to eicosanoids and prostaglandins, signaling molecules that modulate immune system responses and inflammation.

Acid mantle, lipids, proteins and corneocytes combine to create the skin barrier, which is both a physical barrier against outside irritants and a functional barrier against specific bacteria and fungi. The combination of brick-like corneocytes joined together by a lipid-and-protein mortar prevents external water molecules from waterlogging the skin cells, and it also prevents the loss of moisture from within the cells–a phenomenon known as transepidermal water loss (TEWL). 

When any part of this amazing, intricate system malfunctions, the integrity of the skin barrier is compromised–and that brings us to the topic of eczema and the role lipids play in its development and resolution. 

Lipid abnormalities in eczema-prone skin

In both human and mouse studies, numerous changes in lipid content have been identified in skin affected by eczema. LIpid abnormalities disrupt the barrier, which allows irritants or pathogens to penetrate the skin and stimulate inflammation. Inflammation further changes the lipid content of the stratum corneum, contributing to prolonged flares and worsening symptoms.

Abnormal sebum content/inadequate sebum production, decrease of ultra-long chain fatty acids, and abnormal ceramide production (overproduction of some ceramides and deficits of others) have all been documented in studies of both animals and humans with active dermatitis lesions. 

Abnormal sebum production 

People often equate sebum with oily skin and acne, yet this complex product of the sebaceous glands plays many important roles in healthy skin. It contributes to the skin barrier, even offering UV protection. It has anti-inflammatory properties. Recent research suggests that it protects against staph. 

Triglycerides account for a significant portion of sebum’s content. As triglycerides are metabolized in the skin, the glycerol bound to its fatty acid molecules breaks away. Glycerol acts as a humectant, attracting water molecules and helping to maintain moisture in the stratum corneum. It also has antimicrobial properties (you might recognize glycerol by another name–glycerin). 

Sebum production was decreased in tissue studies of atopic dermatitis patients. Patients with the most marked decreases in sebum tended to have the most severe eczema symptoms as rated by the SCORAD (scoring atopic dermatitis) instrument. 

In mouse studies, eczema-like symptoms developed immediately when sebum production was suppressed. The same mice responded favorably when propionate, a key metabolite of sebum, was applied to their lesions. Researchers found that normal sebum production and treatment with propionate modulated signaling by inflammatory interleukins. 

Lack of sebum was associated with greater susceptibility to staphylococcus infection. It was also associated with lowered levels of Corynebacteria and Cutibacteria, lipophilic microbes abundant in healthy skin. These bacteria are thought to offer some protection against staphylococcus and streptococcus.

In other studies, eczema patients were found to have fewer sebaceous glands than subjects without eczema; in addition, existing sebaceous glands were found to be smaller. Similar studies have found a correlation between lowered sebum production and increased TEWL and lowered skin barrier function. 

These studies suggest that lowered sebum production influences the development of eczema in multiple ways; not only does it interfere directly with barrier function, it also appears to disrupt the skin’s microbiome. 

Abnormal Ceramide Content

Studies have found that eczema correlates strongly with decreases in ultra-long chain ceramides and free fatty acids in the stratum corneum. This produces alterations in the extracellular spaces in the stratum corneum, with lipids becoming less dense and more loosely organized. This results in gaps between lipid molecules, leading to weakened skin barrier function.

At the same time, increases in short chain ceramide levels are noted in skin affected by eczema. These changes appear to reduce the stability of keratinocyte membranes. They also reduce the density of the lipid lamellae, stacked layers of densely-packed lipid sheets found in the spaces between corneocytes.  

Some of the ceramides found in higher numbers in eczema lesions have pro-inflammatory properties, while many ultra-long chain ceramides have anti-inflammatory properties.Studies suggest that this alteration could contribute to inflammatory skin disorders. 

At the same time, inflammation itself affects the structure of ceramides in the skin. This could contribute to the development of eczema and exacerbation of symptoms. 

Lowered levels of ultra-long chain fatty acids

A 2002 study reported shortened fatty acid chains in the skin of people with eczema. Short chain fatty acids were found to comprise about 7.7% of the total fatty acids in the stratum corneum; they comprise only 5.4% of total fatty acids in healthy skin. 

Other changes include increases in unsaturated fatty acids, from 20% in healthy skin to almost 30% in the skin of atopic dermatitis patients. Fatty acid chain length affects barrier function. A disproportionate amount of short chain fatty acids and unsaturated fatty acids results in increased permeability and TEWL. 

Long chain fatty acids such as arachidonic acid act as precursors to eicosanoids, which signal for innate immune system responses.While some eicosanoids are inflammatory, others are pivotal in the skin’s defense against bacterial infection. Lowered levels of long-chain fatty acids could therefore play a role in both lowered immunity and heightened inflammation. 

Other changes to lipid composition

Phospholipids are important to the skin barrier. They organize the intercellular spaces and are a necessary part of cell membranes. When they are metabolized, they produce various fatty acids needed to maintain barrier function. 

In normal skin, phospholipids are broken down to allow for the formation of fatty acids. In skin affected by eczema, this break-down is incomplete.

Abnormal cholesterol synthesis is another hallmark of atopic dermatitis. Lower cholesterol levels contribute to TEWL and are thought to influence the development of eczema. 

Summary

Many different lipids are found in the skin–the constituents of adipose tissue in the hypodermis, the sebum produced by glands in the epidermis, and of course, the vast array of lipids in the stratum corneum. Lipids are fundamental to both the function and the structure of the skin. 

When these lipids are not synthesized or metabolized properly, the skin barrier is disrupted. It becomes more permeable, allowing irritants and pathogens a foothold in the stratum corneum. Water molecules evaporate from the skin, leading to dryness. This can trigger eczema flares. 

Changes to the lipid composition of the stratum corneum can trigger inflammation, worsening eczema symptoms; they can also hamper innate immunity and lead to infection. There is a risk of bacterial infection spreading to deeper layers of the skin, which can quickly become serious.

Studies also indicate that lipids could influence the skin’s microbiome. Dysbiosis of the skin is a common problem among people with eczema. 

There are several different ways that the lipids in the skin can impact eczema. Abnormalities in the lipid content of the stratum corneum have been documented by many different studies on the disorder; the lipid abnormalities associated with eczema are so distinct that many researchers believe that they could be used as biomarkers for diagnosing eczema. 

Is there anything you can do about it?

Lipid abnormalities are a part of having eczema, and we don’t fully understand the causes or contributors. There are  ways you can address the issues caused by abnormal lipid composition, though:

• Moisturize!
  In mouse studies, daily application of moisturizers or oils effectively resolved -like eczemalesions. Regular moisturization with a quality moisturizer is vital if you have eczema. Insofar as it can, your moisturizer has to make up for what is lacking in your skin barrier–so look for products packed with ceramides, cholesterol, fatty acids, and humectants such as glycerol. Here are a few ingredients you might want to look for:
  
  
• . Plant oils
  
  Plant oils are becoming increasingly popular in moisturizer formulations. Many have properties of particular interest to eczema sufferers. Coconut oil, for example, has anti-inflammatory and wound-healing properties in addition to its emollient effects.
  
  Jojoba oil’s make-up is remarkably similar to sebum: it contains several fatty acids, including linoleic acid, an essential fatty acidt, oleic acid, which appears to have a strong anti-inflammatory effect on eczema, and arachidonic acid, which is an eicosanoid precursor. It also has waxy esters and triglycerides. Jojoba oil has antibacterial properties, and some studies suggest that it can help regulate sebum production.
  
  Sunflower oil is another plant oil that is becoming popular for skincare. Studies suggest that it has wound-healing properties.
  
  
• Cholesterol
  
  Skincare is one area where you can confidently embrace cholesterol. As an ingredient in skincare products, cholesterol softens the skin and helps slow moisture loss. It appears to improve the skin’s barrier function and to speed up healing. It may even promote normal keratinization (the differentiation process keratinocytes go through).
  
  
• Glycerin (glycerol)
  
  Glycerin is a champion skincare product. It draws moisture to the skin and keeps it from drying out. It also softens skin cells. It brightens the skin and improves its texture. It also has prebiotic properties (more on that later).
  
  
• Prebiotics
  
  Prebiotics (not to be mistaken for probiotics) are ingredients that help balance out the skin’s microbiome–disruptions of the microbiome appear to encourage the development of eczema. Prebiotics make the skin hospitable to beneficial microbes, which helps keep the number of disease-causing microbes in check. Some prebiotic ingredients to look for in moisturizers include glucomannan, alpha-glucan oligosaccharides, inulin, glycerol, xylitol, oats, and flaxseed
  
  
• Triglycerides
  
  Triglycerides are one of the principal constituents of sebum. They soften the skin and have antimicrobial properties. You may find it on ingredient labels as capric acid or caprylic triglycerides.
  
  
• Ceramides
  
  About 50% of the lipids in your stratum corneum are ceramides. They are necessary parts of the skin’s barrier function. On labels, they’re often listed simply as “ceramides.” They might also be listed as ceramide 1, ceramide 3, etc. The manufacturer might also list it as sphingosine. 

There are many well-loved moisturizers that contain these compounds. AveenoⓇ is gentle on sensitive skin, and it offers oat–a prebiotic–as an ingredient. CeraVeⓇ is a longstanding favorite of dermatologists. Perfect Repair ™ is a newer lotion, released by HarlanMD in 2023. It was created by Steve Harlan MD, a board-certified dermatologist especially for people affected by eczema. It includes all of the ingredients mentioned above; it’s filled to the brim with ceramides, and it contains both coconut oil and jojoba oil.

Add serums to your skincare. In addition to your moisturizer, consider adding some moisturizing serums to your routine. Hyaluronic acid serums are effective and popular. Apply them to damp skin and allow your skin in 2-5 minutes to absorb the serum before adding moisturizer

Try oil cleansing. Oil cleansing involves the use of vegetable-based oils to cleanse the skin and add emollients, and many dermatologists are embracing it.

Choose an oil appropriate for your skin: grapeseed, argan, and coconut oils are usually better for acne-prone skin, while avocado, jojoba, and sunflower oil are better suited for use on dry skin.

To cleanse, place at least a teaspoon of oil into your palm. Using your fingers, rub the oil into your skin. Rinse with warm water or a warm, wet cloth. Pat dry and apply serums and moisturizers as usual. 

Add healthy fats to your diet. Your body relies on fatty acids to synthesize other molecules, including some of the lipids in your stratum corneum. Some fatty acids, though, cannot be produced(or cannot efficiently be produced) by the human body and must be obtained through diet. This includes linoleic acid, alpha-linolenic acid, and Docosahexaenoic acid (DHA).

Walnuts, flaxseeds, spinach, fatty fish such as salmon or cod, and soybean oil all contain essential fatty acids. Some studies suggest that supplementation has benefits, as well.

Some common practices have a deleterious effect on the lipid content of your skin. Here are some things to avoid if you are trying to improve the lipid balance in your skin :

• Taking long, hot showers/baths. This strips away the protective oils in your skin and dries it out. Take brief showers–less than 20 minutes–and keep the temperature comfortably warm. 

• Using harsh cleansers and toners. Avoid products where alcohol is among the first five or ten ingredients. They cut through the lipids in your stratum corneum and increase TEWL..
  
  
• Exfoliating too often. Exfoliation is good for your skin, but it needs to be done properly. It shouldn’t be done daily, it shouldn’t be done when your eczema is flaring, and it shouldn’t be done with harsh chemicals or scrubs. While exfoliation can promote healthy keratinocyte turnover, doing it too often disrupts your skin
  
  
• Extreme dieting, especially diets that eliminate fats. By now, you should recognize that you need fats and oils in your diet. Eliminating healthy (polyunsaturated) fats will take a toll on your skin over time. While diet alone cannot cause eczema, it can disrupt the balance of lipids and other nutrients in your body. Skin will dry out much more quickly if you do not add some healthy fats to your diet.
  
  
• Smoking. Studies have found that smoking disrupts the balance of lipids in the skin, and it may lead to increased inflammatory signaling. 

Conclusion

Lipids are fatty, oily, or waxy compounds made of one atom each of hydrogen, carbon, and hydrogen. Most lipids are made of fatty acid chains–steroids are the exception. This group of molecules plays several key roles in your skin. Some provide a mechanical defense against irritants or harmful substances in your environment. Others facilitate the function of signaling molecules in the epidermis. Some lipids have antimicrobial properties, some modulate inflammation, and others stimulate the immune system. 

People with eczema have flaws in their lipid composition. This leads to inflammation, TEWL, and increased susceptibility to staph. Moisturization appears to relieve eczema symptoms in animals and humans alike.

By eating a well-rounded diet and practicing good skincare, you can mitigate the effects of disrupted lipid metabolism. 

 

 

  Cee Van

  Medical Writer

  HarlanMD.com

 

 

 

 

Sources

• https://www.sciencedirect.com/science/article/pii/S0022227520404006?ref=pdf_download&fr=RR-2&rr=8426bf057b81b0d3

https://www.walkinlab.com/blog/what-are-lipids/

https://www.sciencedirect.com/science/article/pii/S0022227520339687#:~:text=Additionally%2C lipids have been broadly,yielding three or more products

https://www.physio-pedia.com/Lipids

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