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The other component to healthy skin-barrier function is natural moisturizing factors (NMFs). NMFs are found in the corneocytes of your stratum corneum and make up about 20–30% of the dry weight of your stratum corneum.
Common NMFs in your skin are sodium PCA, lactic acid, free amino acids, and urea.
You can divide moisturizers into three categories of ingredients based on their function: humectants, emollients, and occlusives.
Humectants are water-grabbing ingredients that help your skin maintain a healthy moisture level, which is key to maintaining that desirable, supple feel.
Some gold-star humectants used in moisturizers are glycerin, hyaluronic acid, and glycols.
Emollients fill in the rough patches of your skin and instantly give it that soft, smooth feel. These ingredients are usually lighter, oil-based substances such as jojoba oil, caprylic/capric triglyceride, squalane, and coconut alkanes.
Occlusives are heavy, fatty, waxy substances that form a physical, water-resistant barrier over your skin to seal in moisture. Some common occlusive ingredients are petrolatum, butters, waxes, and heavier silicones.
UREA (Molecular weight: 60)
LACTIC ACID (Molecular weight: 90)
GLYCERIN (Molecular weight: 92)
PANTHENOL (Molecular weight: 205) Also known as pro-vitamin B5
Hydration is measured by a corneometer; this handheld device tracks skin’s dielectric (insulative or nonconductive) properties, and reports hydration as a percentage. In a study, you’d typically measure this value on clean skin, moisturized skin, and skin several hours after product application to assess how hydrating a product is.
Remember: TEWL (pronounced like tool) stands for Transepidermal water loss. As the name suggests, it’s how much water evaporates out of your skin. The higher the TEWL rating, the worse the skin barrier. This is a really useful way to test several different claims. For example, the tester may purposely damage a patch of skin to create an area with a high TEWL, then apply a particular cream to bring the value back down. Neat, eh?
PETROLATUM (good ol’ Vaseline)
MINERAL OIL
LANOLIN This is a great occlusive derived from wool. It can be an allergen, though, so look for medical-grade lanolin
You’ll find a lot of coconut-derived stuff, but not all are created equal. For example, caprylic and capric triglyceride are light esters derived from coconut oil. These light emollients are generally friendly to oily skin.
WAXES More great occlusives that often come from natural sources such as beeswax, candelilla, carnauba, and others.
How do you spot a silicone gel cream? Look for terms such as dimethicone or “dimethicone crosspolymer” fairly high on the ingredient list.
Lips could really use their own products. Not only is lip skin found to have a thinner SC, but it’s also completely devoid of sebaceous glands and skin pigments. Petrolatum, lanolin, and other heavy occlusives help protect the skin from the elements. Since lips don’t have melanin, consider a lip balm with SPF during the day!
Body skin is relatively resilient and durable, so a simple drugstore lotion will suffice. As you get older and your skin cell turnover slows down, dry skin will become a bigger issue, so look for body lotions with lactic acid and urea to help the skin barrier.
Seek out helpful skin barrier–supporting ingredients. Lipid-mimicking ingredients like ceramides, cholesterol, and fatty acids can really help elevate your moisturizer game and get your skin back on track. Ceramides in particular can help strengthen your skin barrier, help it retain moisture, and even protect from outside environmental aggressors.
The mid-length wavelength, UVB makes up 5% of the UV that reaches our skin. Because of a shorter wavelength in comparison to UVA, this only reaches the epidermis. UVB is responsible for sunburns and delayed tanning, and is the main culprit of skin cancer.
UVA The longest of the three wavelengths, UVA makes up 95% of the UV that reaches our skin. UVA can reach all the way down to the dermis and is responsible for deep photoaging and enhanced skin cancer development. We always remember the two as B is for Burns, A is for Aging.
This means that an SPF 15 sunscreen blocks roughly 93% of UVB, while an SPF 30 sunscreen blocks about 97% of UVB.
Chemical sunscreen filters oxybenzone and octinoxate are banned in Hawaii due to their impact on the coral reef. Studies have shown that not only do these two filters cause coral bleaching, they also inhibit coral reproduction and cause deformation in young coral.
Chemical exfoliants: Acids such as glycolic, lactic, and mandelic, which gently dislodge dead skin cells that have overstayed their welcome.
Chemical means they are acids that weaken the bonds (proteins called corneodesmosomes, should this ever come up at trivia night) between dead cells that have overstayed their welcome, which helps your skin return to a healthy turnover rate. Shedding the top layer of cells has the short-term benefit of smoothing skin texture. In the long run, some of these ingredients can even help tackle pigmentation, acne, and even—gasp—collagen production!
AHA category includes glycolic, lactic, mandelic, malic, and tartaric acids. These are water-soluble, weak acids. Of these acids, we’ll only focus on three: glycolic, lactic, and mandelic. The main difference between these three is their molecular size,
PHA typically refers to two molecules: lactobionic acid and gluconolactone, with gluconolactone being the much more common one in skincare. It’s said to be an ultragentle chemical exfoliation experience, and even acts as a humectant, keeping hold of water and hydrating skin. In fact, it’s so gentle that it doesn’t even make your skin sun sensitive, unlike the others.
The smaller the molecule, the more aggressive yet effective.
For effective daily upkeep, here’s what to look for on labels: 5–10% glycolic acid > 8% lactic and mandelic acids 0.2–2% salicylic acid 10% gluconolactone The product’s pH: For AHA/PHA products, the lower the pH, the better it works.
pH adjusters: These ingredients—which include sodium hydroxide, potassium hydroxide, and triethanolamine,
your AHA wipe, toner, or serum (pick one!) should fall into either step 1 or 2 of your nighttime routine, right after cleansing. Products with a concentration of under 10% AHA can be used daily. If you’re sensitive to even a lower concentration, use it on alternate nights.
to add a high-level (20% or more) product to your skincare arsenal. These higher-concentration AHA products should be used as rinse-off masks no more than once a week.
Start with 10-14% gluconolactone 10% mandelic acid 5-10% lactic acid 5-10% glycolic acid * Remember, if at any given point you find yourself encountering scenario 1, stop all actives use and focus on getting skin back to its healthy self.
Collagen actually makes up roughly 75% of the dry weight of your skin. With its tight-knit, triple-helix structure, it is responsible for the skin’s overall structural integrity. As such, the loss of collagen over time is a root cause of wrinkles and sagging.
Enter fibroblasts: These cells not only play a critical role in wound healing, they also secrete procollagenase, a precursor that acts as building blocks, which are cross-linked
late 1960s when Dr. Albert Kligman, Dr. James Fulton, and Dr. Gerd Plewig invented tretinoin.
retinoic acid, retinol, and retinyl palmitate are all part of the bigger retinoids family.
Then, in 1992, Dr. Sheldon Pinnell, founder of Skinceuticals, pioneered and concocted the famed CE ferulic combination, earning an iconic (and now-expired) patent. Since then, the vitamin C serum has become a staple in many people’s anti-aging skincare routines.
natural antioxidants: CoQ10, glutathione peroxidase, superoxide dismutase, vitamin E, uric acid, carotenoids, melanin, and vitamin C.
L-ascorbic acid, or L-AA (pure vitamin C) is the reigning, gold standard skincare antioxidant.
Very few ingredients actually have been proven to boost collagen, and since collagens are the pillars of your skin’s structural integrity, this explains why ascorbic acid also helps with minimizing fine lines and wrinkles.
In a nutshell: The three main benefits L-AA offer are photoprotection, brightening skin tone, and boosting collagen. With this trio of benefits, L-ascorbic acid can be considered both a preventative and a direct anti-aging fighter. It can deliver both short-term, visible improvements, like improved skin tone and clarity, and long-term anti-aging benefits.
Vitamin E (ingredient name tocopherol) and ferulic acid are both antioxidants as well. The trio works together synergistically. Including vitamin E and ferulic acid in your serum along with vitamin C not only slows down vitamin C degradation, it also enhances the free radical–fighting power of the entire formula.
Is your top skin concern anti-aging? We recommend going to sodium ascorbyl phosphate next. Is your top skin concern pigmentation? We recommend trying ascorbyl glucoside.
Studies have shown that creams with as little as 2% niacinamide can improve skin moisture and overall skin-barrier function in the long run.
Niacinamide is actually one of the few ingredients out there that has demonstrated long-term sebum-regulation effects when used consistently at topical concentrations of 2-4%.
active as an effective acne treatment that can even help reduce the appearance of pores.
