that smaller HAs can penetrate the skin to plump, hydrate, and even bring
anti-aging benefits. However, some people can be sensitized by these
small HAs. So, as we always say: Patch-test, patch-test, patch-test (Chemists’
Commandment #9).
Emollients and Face Oils
Over the years, face oils have gained a lot of popularity, and every brand
is brewing its own version. You’ll find that they all seem to be 100% pure,
100% organic, 100% potent, and 100% exaggerated. Regardless of the claims,
face oils are a great addition to your routine to boost nourishment, add glow
“X% OF PEOPLE AGREE, SKIN FEELS MOISTURIZED” “STAY MOISTURIZED
FOR 24 HOURS!” “SKIN IS 75% MORE HYDRATED!”
Do these common moisturizer claims sound like random numbers yanked out of some
marketing exec’s behind? It turns out these claims are actually backed up by scientific studies.
Most moisturizer studies look at two values: hydration and TEWL.
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?
DECODE That Claim
SKINCARE DECODED • 54 MOISTURIZERS • 55
to dull skin, smooth skin surface, and improve overall skin pliancy. While
oils are lousy stand-alone moisturizers, there are a few key scenarios where a
face oil can really elevate your skin routine.
FACE-OIL-TO-THE-RESCUE SCENARIOS
Consider a face oil for the following scenarios:
“I love my moisturizer, but my skin still gets a little dry.” Skin constantly
changes. Just from stress, age, lifestyle, and hormones, your moisturizing
requirements can really fluctuate. If you’re loyal to your moisturizer and know
your skin needs just a little help in the moisturizing department, consider
adding a couple of drops of face oil to give it that oomph.
“I’m dry, but not petrolatum/balm (cactus) dry.” We get it—petrolatum and
other heavy-duty occlusives feel kind of gross. Not to mention the disco-ball-
shiny look is so not in right now. Consider face oils, their lighter (albeit less
effective) cousins.
“My skin is a little dull.” A quick way to add back that healthy glow to skin is
with a couple of drops of face oil.
“I have acne, but my acne topicals are drying me out, and my current
moisturizer isn’t cutting it.” Look for a lightweight emollient such as linoleic,
acid–forward plant oils or squalane.
Representative Emollient-Forward Product Face oils
New to oils? Consider squalane
Before you try to figure out if you need rose hip, watermelon seed, argan, or whichever plant
oil, consider squalane, which is a purely saturated hydrocarbon. In laypersonʼs terms, this
means that it’s super vanilla and is highly unlikely to irritate you or cause you to break out. It’s
a great starting point for beginners of all skin types.
MOISTURIZERS • 57
Face Oil Shopping Guide
Donʼt know where to start?! Here are a few popular oils organized with some chemist notes:
DRY
SWEET ALMOND OIL
Youʼll find this in everything,
even $$$ serums.
APRICOT KERNEL
ARGAN
AVOCADO
CAMELLIA
Often used in Asian skincare brands.
JOJOBA
MACADAMIA NUT
MARULA
MORINGA
OLIVE
SHEA
Can come in either butter or oil form.
OILY
BLACK CURRANT
CHIA
CRANBERRY SEED
EVENING PRIMROSE
Easily oxidizes. Use it quickly.
GRAPE SEED
HEMP SEED
This is not CBD.
MARACUJA SEED
a.k.a. passion fruit seed.
PRICKLY PEAR
ROSE HIP SEED
SEA BUCKTHORN SEED OIL
Make sure this isnʼt the fruit oil; it stains.
SQUALANE
Great intro to oils; pretty vanilla.
Great for dry skin, too.
Meet Mr. Vampire. He will remind you to store in his preferred setting—cool, dark,
and well sealed. That’ʼs right: Oils oxidize and go rancid. Rancid oils change color
and smell off. They can end up causing trouble for your skin.
MOISTURIZERS • 57
Occlusives
Occlusives are your butters, waxes, and petrolatum. As the name suggests, they
help shield your skin from the elements. When your skin-barrier function is
compromised, occlusives help protect skin and seal in moisture. The catch is
that occlusives can feel heavier and greasier than the other categories. People
with oily skin need lighter gel creams that contain little to no occlusives, while
those with dry skin may want to opt for a heavier cream that has more. We do
always recommend having an occlusive balm (think Vaseline, Aquaphor, and
the like) to spot-treat those troubled areas!
PETROLATUM (good ol’ Vaseline)