Why Your DIY Skincare Doesn’t Work
Just grease it - isn't the way to moisturize your skin
As a notoriously dry skinned individual, I have tried everything from my grandmom’s favorite Vaseline to my Mom’s method: do nothing and pray, your skin will heal itself. It does not. I’ve also tried at least 15 DIY recipes and solutions - from all types of oils to homemade body butters with shea butter, mango butter and cocoa butter.
After all that….
I always come back to Nivea Cold Cream.
Which made me wonder: What’s in this stuff that my homemade salves and body butters are just not able to deliver?
Before we can talk about a good moisturizer, we need to talk about what they are moisturizing, and the mechanisms at play.
Anatomy of the Skin: The parts that matter most for moisture
Skin is a layered system with each layer playing its own role in how your skin looks and feels.
For moist skin, the most important parts are:
Stratum corneum:
This is the top layer of your skin, the part you can touch. It’s mostly made of dead skin cells surrounded by barrier fats: ceramides, cholesterol, and fatty acids. This layer’s main job is to keep things out of the body and to control how much water escapes from your skin.
When the stratum corneum is healthy, skin feels smoother, softer, and more comfortable. It holds onto water better.
When it is damaged, water escapes too quickly. That is when skin starts to feel tight, rough, flaky, stingy, or dry - even if you are drinking enough water.
Epidermis
Under the stratum corneum is the rest of the epidermis.
This is where your skin is constantly making new cells. Those new cells start deeper down, then slowly move upward. As they rise, they flatten, lose their nucleus, and eventually become part of the stratum corneum.
That process is called skin turnover.
When turnover is working well, the surface of your skin tends to look smoother and more even. When turnover slows down (due to aging,hormonal changes, stress, illness or undernutrition), dead skin cells can build up unevenly, making skin look dull, rough, flaky, or patchy.
This is also where melanocytes live. These are the cells that make pigment, which is why tanning, dark spots, and uneven skin tone often involve the epidermis.
The epidermis is the active layer - constantly rebuilding the surface you see.
Dermis:
The dermis is below the epidermis. This is the thicker, deeper layer. This is the part that is connected with the rest of the body. It contains collagen, elastin, blood vessels, nerves, sweat glands, oil glands, hair follicles, immune cells and naturally occurring hyaluronic acid and other water-binding molecules
The dermis gives skin its firmness, bounce, thickness, elasticity and plumpness.
How water moves through the skin:
Water moves roughly like this:
bloodstream → dermis → epidermis → stratum corneum → evaporation
The dermis receives water from inside the body.
The epidermis transfers and organizes it.
The stratum corneum decides how much stays.
The environment decides how fast it evaporates.
Water is always moving upward and evaporating from the skin surface. That is normal.
Your skin feels moisturized when there is a good balance between: water arriving from inside and water not escaping too fast
Because the body does not treat “glowy skin” as the top priority - when you are dehydrated, it will show on your skin first!
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How a good moisturizer works:
A good moisturizer does not just slap oil on your skin. It helps your skin manage water: pulling it into the top layers of skin, smoothing the barrier, and helping to hold the water in your skin, preventing the water from escaping.
The main types of ingredients in a moisturizer are:
Water
Sometimes it makes up 60-80% of the formula! It’s often the first ingredient on the list.
Water has multiple functions in a moisturizer - firstly some of this water is absorbed by your skin. This little bit of water makes your skin instantly feel better. Its second job is to carry and deliver humectants (explained next).
Most of it will just evaporate away, which is why just putting water on your skin can make your skin feel drier and tighter.
Humectants:
As a food scientist, I use humectants to help keep bread and protein bars moist - and turns out some of the ingredients that help protein bars stay soft will help your skin too! Humectants attract and bind water.
You’ll see this on a label as glycerin, hyaluronic acid, sodium hyaluronate (salt form of hyaluronic acid), urea, panthenol (pro-vitamin B5), lactic acid, lactate, or sodium PCA.
They can help pull water from the deeper layers of your skin into the top layer of your skin. They work best when paired with ingredients that seal the water in (occlusives coming up).
Otherwise, in very dry air, some humectants can dry your skin our even further when not paired correctly with occlusives.
2. Emollients: smooth and soften
Emollients fill tiny gaps between dry, rough skin cells. They make skin feel smoother and more flexible.
Examples: squalane, plant oils like: jojoba oil. Olive oil, avocado oil, plant butters like shea butter, cocoa butter, mango butter, fatty alcohols, esters (palmitaties), Silicons, ceramides, linoleic acid.
These do not necessarily add much water. They make the skin surface feel softer and help fill in gaps between the skin cells, helping to form a better barrier for the water as it tries to leave the skin.
3. Occlusives: seal water in
Occlusives form a protective layer on top of the skin that slows evaporation. They don’t add any hydration themselves, but they prevent the moisture that is in your skin from leaving. They make the moisturizer last longer which is why the “long lasting” moisturizers will have a higher percentage of these.
This includes things like: petrolatum, mineral oil, dimethicone, lanolin, beeswax, shea butter and heavier oils
Petrolatum is one of the strongest occlusives. It does not “hydrate” by adding water; it prevents your own water from escaping. Turns out my Grandmom was onto something - vaseline is an important step in the moisturizing process!
A good moisturizer usually combines all 4
A well-designed moisturizer often has:
Water + humectant + emollient + occlusive
A lot of the magic is in picking the right balance of these to give your skin the perfect feeling of hydration, softness, lasting moistness without the greasiness. And ofcourse - the marketing, the packaging and the feel good factor.
As someone who has worked with clean label formulations my whole life, I understand why synthetic chemicals sound scary. But if you look at the actual science, the multi-billion dollar clean beauty movement starts to look like a massive marketing upcharge.
Coming up on Thursday is a closer look at the moisturizing industry, the myths, the facts, and what to look for when buying them!