Science Behind Moisturizers: Mechanisms, Uses, and Benefits
Maintaining
your skin healthy is important for your general health as well as
appearance. Moisturizers are one of the
most popular preparations in cosmetics and have been utilized extensively to
make skin softer and more resilient. Contemporarily, dry skin wrinkles, pain,
tightness, itching, and stinging, can be efficiently treated with moisturizers.
It also preserves water balance, which clarifies the importance of water in the
stratum corneum (stratum corneum is the outermost layer of the epidermis) that
keeps dangerous substances out of the body and stops water loss, as well as
maintaining healthy skin physiology and turnover processes (1, 2).
History of Moisturizer
Cosmetics
have undoubtedly been around for far earlier, the earliest evidence of them comes
from Ancient Egypt, around 6000 years ago. Egyptians frequently use
frankincense, myrrh, and aloe. The ancient Egyptians employed these materials
as anti-wrinkle lotions because they thought they had anti-aging qualities,
especially frankincense (1).
Mechanisms of Action:
Moisturizers
function by nourishing the skin and re-establishing its natural barrier
function. The humectants, occlusive agents, and emollients found in
moisturizers combine to increase skin hydration and stop water loss. Glycerin
and hyaluronic acid are examples of humectants that draw water to the skin and
contribute to its increased water content. Mineral oil and petrolatum are
examples of occlusive substances that create a physical barrier over the skin
to prevent water evaporation. By filling the spaces between skin cells,
emollients like ceramides and shea butter help to soften and smooth the skin
(2, 3).
Types of Moisturizers
2. Occlusive moisturizers: Occlusive
moisturizers establish a barrier that prevents water loss or lowers
transepidermal water loss (TEWL) from the skin. Because of this barrier, the
deeper layers of the epidermis and dermis can refill the level of water in the
stratum corneum. The most successful occlusive moisturizer is petroleum oil,
which reduces water loss through the epidermis by over 99%. Many other
substances can serve as occlusive moisturizers:
Hydrocarbons:
Petrolatum, mineral oil, paraffin, squalene
Silicones:
Dimethicone
Vegetable
oils: Coconut oil, castor oil, olive oil, grape seed oil, soybean oil
Animal Fats:
Mink oil, emu oil, lanolin
Wax Esters:
Lanolin, beeswax
Sterols:
Cholesterol, ceramides
2. Humectants: Humectants are substances that draw in and
hold onto water. Among these, urea is an endogenous molecule that makes up the
natural moisturizing factor (NMF). More often, humectants pull water from the
deeper layers of the epidermis and dermis, but they can hydrate the skin if the
humidity is higher than 70%.
Urea is one of the key components of NMF. Urea is added to
moisturizers to aid in water absorption into the stratum corneum. It encourages
corneocyte desquamation and improves the absorption of other topically
administered drugs.
Glycerin is another commonly used humectant and it is
frequently present in many skincare products. It has positive effects on
barrier repair in addition to absorbing and binding water. Honey, sorbitol,
propylene glycol, and hyaluronic acid are further humectants.
3. Emulsifiers: Emulsifiers are crucial ingredients in many
skincare products, enabling the stable combination of oil and water-based
components. While they enhance product texture and facilitate ingredient
absorption, but some emulsifiers can potentially disrupt the skin’s natural
barrier, leading to dryness, irritation, and even conditions like contact
dermatitis. Hence, it selection is equally important as other active
ingredients of the moisturizer. Commonly used emulsifiers are fatty acids, like
stearic acid.
Choose Moisturizer Based on Your Skin Type
Dry Skin
A moisturizer
containing rich, nourishing ingredients like lycerine, ceramides, and shea
butter is essential for people with dry skin. Since lightweight or gel-based
moisturizers might not sufficiently hydrate skin that is very dry, consumers
should stay away from using them. A thicker-textured moisturizer, like ointment
or lotion, aids in preserving moisture (1, 2, 3).
Oily Skin
A
lightweight, oil-free moisturizer is the best option for people with oily skin
because thick, greasy lotions can block pores and lead to illnesses.
Individuals should look out for a moisturizer that contains moisturizing yet
non-greasy components like lycerine or hyaluronic acid. In my opinion,
gel-based moisturizers are typically lighter and easier to absorb, they ought
to think about using one (2, 3).
Sensitive Skin
Sensitive
skin types should check out moisturizers that are hypoallergenic and
fragrance-free because they are less likely to cause irritation. They should
stay away from moisturizers with harsh chemicals or preservatives and instead
pick one with calming elements like chamomile or aloe vera (2, 3).
Mature Skin
Our skin
tends to get thinner and drier as we mature. Hence, in older age, skin texture
can be enhanced and wrinkles and fine lines can be lessened using moisturizers
that include retinol or peptides. For deeper hydration, older adults should use
a moisturizer with a heavier consistency, like an ointment or cream (2, 3).
Best Practices for Moisturizer Use
Application Timing
Apply
moisturizer when the skin is slightly damp or moist (e.g., after bathing) to maximize
hydration and seal in moisture.
Product Selection
Choose
moisturizers with ceramides, humectants (like urea, and lycerine), and
emollients for optimal barrier support. Acidic formulations are particularly
beneficial for maintaining the skin’s natural pH and supporting the microbiome.
Gentle Cleansing
Use lukewarm
water and mild, fragrance-free soaps to avoid stripping the skin of natural
oils and exacerbating dryness or irritation.
Summary
More than
just beauty goods, moisturizers are vital resources for preserving the
integrity of the skin’s barrier, treating dermatological disorders, and
promoting skin health. As per the extensive research, I have concluded that
every person should choose formulas that are supported by research for optimal
effects, and use them frequently on wet skin, especially after washing it
gently with lukewarm water and light soaps for better results.
References
(1)
A review of moisturizers; history, preparation,
characterization, and applications. Cosmetics. 2022.
(2)
Moisturizers, Starpearls Book. 2024.
(3)
The role of moisturizers in addressing various kinds of
dermatitis: a review. Clinical medicine & research. 2017.