characteristics such as suppleness, sagging, and
even wrinkle formation. Fun fact! A lot of anti-aging
ingredients are tested on cells found in the dermis.
Collagen & Elastin The structural
proteins that hold your skin up. Losing
this support over time is what
creates fine lines and wrinkles.
Fibroblasts Fibroblasts giveth, and
fibroblasts taketh away. Think of them as
the architects of your skin, responsible for
a wide range of skin functions, including
building and destroying collagen, handling
inflammation, and even healing wounds.
You Are Here
SKINCARE DECODED • 18 BASICS 101 • 19
Hypodermis The innermost (or deepest)
and thickest layer of skin, also known as the
subcutaneous layer or subcutaneous tissue.
Dermal-epidermal junction A key
player in the aging process. As this
structure changes, it starts a cascade
effect limiting the interaction between
the dermis and epidermis and leads to
sagging and wrinkle formation.
SKINCARE DECODED • 20 BASICS 101 • 21
Skin Types
Y
our skin most likely falls into one of the three
main categories below. In actuality, most people
will cover the entire spectrum of skin types in their
lifetimes. Skin changes because of changes in lifestyle,
climate, stress, hormones, aging—basically, life! While
the thought of micromanaging your routine through these changes may sound
daunting, you may only need a couple of minor adjustments to your routine to
keep up with your skin’s changes and get it back on track.
But first, a very important question: What skin type do you have?
Dry Skin (scientific term: xerosis)
Think tightness, flaking, roughness, itchiness, and an overall lack of pliability.
It’s simply because there’s a lack of fluids in your skin. In science terms, this
happens when there’s a disruption of the fatty lipid matrix in the stratum
corneum—causing water to evaporate out of your skin at a faster-than-normal
rate. This kicks off a cascade of unfortunate events. Skin can become thicker
(and not in a good, plump, collagen-full kind of way) as the process of sloughing
off dead corneocyte cells slows down. This slowdown leads to that undesirable,
rough, uneven texture and dull appearance. Unfortunately, skin tends to
become dryer and dryer as you age. But not to fear! As chemists, the core of our
job is to make moisturizers that can tackle this problem. We gotchu, fam!
Key Traits
Characteristics Skin feels tight, dry, and flaky, has a rough texture, and may
even feel itchy.
Pros Minimal acne and blackheads, and you can get layer-happy with your routine
if you want to.
Cons Flakiness, uneven texture, fine lines, and wrinkles. These issues are often
exacerbated by several factors: the climate you live in, plane rides with close to
zero moisture, seasonal changes, and aging!
SKINCARE DECODED • 20 BASICS 101 • 21
Normal Skin (scientific term: . . . skin)
There’s a lucky subset of you who have skin that seems just fine: normal, healthy,
and hydrated. Skin is bouncy, your skin tone is bright, and you’re neither flaky
nor oily, because you’ve got that coveted optimal water concentration in the
stratum corneum. Lucky you—carry on! That doesn’t mean you won’t experience
unwanted skin changes here and there when life throws new challenges your way.
But you already have a fantastic starting baseline! (Jump to our age-prevention
recommendations on page 204 to keep your skin the subject of envy for life.)
Oily Skin (scientific term: seborrhea)
The light shines just right, and you can’t help but feel like you’re a disco grease ball?
Oily skin is characterized by excess sebum, or oil, production due to enlarged seba-
ceous glands. Sebum is produced by the sebaceous glands connected to your hair
follicles. This is why acne is often linked to oily skin types. Men tend to have oily skin
due to higher levels of testosterone.
Although you may find excess sebum production kind of gross, sebum
actually plays an important part in overall skin health and immunity. Via
sebum, the skin is able to produce fat-soluble antioxidants and provide an
antimicrobial layer. Another misconception is that having oily skin means that
you don’t have to use moisturizers. While it’s true that sebum can indirectly
help SC hydration, sebum production and skin hydration are actually
independent of one another. That’s because sebum production doesn’t involve
the lipid matrix, which prevents water evaporation, it involves the sebaceous
glands found in the hair follicle. (Refer to the skin diagram to help visualize the
difference between the sebum gland and the lipid matrix.) Thus, more sebum
output doesn’t entirely correlate to a higher ability for the SC to retain water in
the skin. Short version? Oily skin can still be dehydrated.
Key Traits
Characteristics Excess sebum, acne, blackhead congestion, large pores, shiny
skin by late afternoon, and a general feeling of wanting to wash your face too
many times.
SKINCARE DECODED • 22 BASICS 101 • 23
Pros Since skin tends to be better hydrated, people with oily skin often have
fewer issues with fine lines and wrinkles.
Cons Inconvenient. You’re conscientious of how shiny you look for that dinner
date. Random breakouts before that speech you have to give. Finding products
takes some finagling.