Tallow has become one of the most talked about ingredients in skincare.
Some people describe it as almost identical to human skin. Others claim it can rebuild the skin barrier, increase collagen, heal acne, or replace an entire skincare routine.
The truth is a little less dramatic and actually more interesting.
Tallow has properties that make it a beautiful emollient for dry skin, but research specifically studying cosmetic beef tallow on human skin is still limited.
So let’s talk about what we actually know.
First: What Is Tallow?
Tallow is rendered animal fat.
At Twin Tallow, we start with locally sourced Arizona beef suet from grass fed, grass finished, pasture raised cows.
Suet is the dense fat found around the kidneys. Through slow rendering and purification, that raw fat becomes the smooth, creamy tallow used in our skincare formulas.
From a skincare perspective, what makes tallow interesting is its lipid and fatty acid composition.
Beef tallow naturally contains fatty acids including:
Oleic acid
Palmitic acid
Stearic acid
These fatty acids contribute to tallow's rich texture, spreadability, and emollient properties.
But before we go any further, there is an important distinction:
Tallow is not the same thing as the skin's natural lipid barrier.
And it doesn't need to be.
Meet Your Skin Barrier
To understand what tallow can do, we first need to understand where skincare actually meets your skin.
The outermost layer of the epidermis is called the stratum corneum.
Think of it a little like bricks and mortar.
The "bricks" are flattened skin cells called corneocytes.
Between those cells is an incredibly organized lipid matrix made primarily of:
Ceramides
Cholesterol
Free fatty acids
That lipid matrix is a huge part of what makes your skin a barrier.
It helps keep water inside while helping protect the body from irritants and other things in the outside environment.
When that barrier isn't functioning well, skin can feel dry, tight, flaky, rough, irritated, or unusually sensitive.
So Where Does Tallow Fit?
Tallow doesn't replace your skin's natural ceramides or magically recreate the lipid structure of the stratum corneum.
Instead, think of tallow primarily as a lipid-rich emollient.
Emollients help soften and smooth the skin by filling some of the spaces around dry, rough surface cells and leaving the skin feeling more supple.
A lipid-rich balm can also create a layer over the skin that helps support moisture retention.
And that brings us to one of my favorite skin-barrier topics:
TEWL
TEWL stands for transepidermal water loss.
Your skin is constantly losing a small amount of water to the environment.
That is normal.
But when the skin barrier becomes compromised, water can escape more easily.
In skincare research, increased TEWL is commonly used as one indicator of impaired barrier function.
This is one reason moisturizers matter.
Different moisturizing ingredients work in different ways.
Humectants attract and hold water.
Emollients soften and smooth the skin.
Occlusive ingredients help slow water evaporation from the skin's surface.
Many products use a combination of all three.
Tallow is especially interesting for its emollient, lipid-rich character.
That makes it particularly appealing in simple, waterless balms designed for skin that feels dry, depleted, or easily stripped.
What About Tallow's Fatty Acids?
This is where skincare marketing sometimes gets a little ahead of the science.
You'll often hear that because tallow contains fatty acids also associated with human skin, it is "bioidentical" or almost identical to our natural sebum.
That's an oversimplification.
Tallow and human skin are not compositionally identical.
But the fatty acids in tallow still influence how it behaves on the skin.
Oleic Acid
Oleic acid contributes to the soft, rich, spreadable quality of tallow.
But more is not automatically better.
Research using isolated oleic acid has shown that it can disrupt the organization of the stratum corneum and increase permeability under certain experimental conditions.
That doesn't mean a tallow balm is inherently barrier-damaging.
Tallow is a complex triglyceride mixture — not a bottle of isolated oleic acid.
It does mean we shouldn't take one individual fatty acid and label it universally "barrier repairing."
Skin biology is more complicated than that.
Stearic Acid
Stearic acid is a saturated fatty acid that helps give tallow some of its structure and body.
From a formulation standpoint, it contributes to that smooth, substantial, cushiony texture you feel in a balm.
Palmitic Acid
Palmitic acid is another saturated fatty acid found naturally in tallow.
It contributes to tallow's lipid-rich character and the soft, conditioned feeling it can leave on the skin.
Again, the value isn't that one fatty acid is doing something magical.
It's the whole formulation and how it behaves on the skin that matters.
Does Tallow Repair the Skin Barrier?
This is where wording matters.
We have strong evidence that the skin barrier depends on its own highly organized system of ceramides, cholesterol, and free fatty acids.
We also have extensive evidence that appropriate moisturization can help improve dry skin and reduce water loss.
What we do not currently have is a large body of controlled human trials showing that topical beef tallow itself reconstructs the skin's native lipid architecture.
So I don't tell you that tallow "rebuilds" your barrier.
I think the more accurate way to describe it is this:
Tallow can act as a rich emollient that helps soften the skin and support moisture retention while the skin's own barrier continues doing the biological work.
That's still valuable.
It just isn't magic.
What Does the Research on Tallow Actually Look Like?
A 2024 peer-reviewed scoping review specifically looked at the existing research on rendered animal tallow and skin.
Researchers screened 147 studies, but only 19 met their criteria for inclusion.
Those papers included basic science, comparative studies, and animal research.
Their conclusion wasn't that tallow doesn't work.
It was that we need much better human research specifically studying tallow as a cosmetic skincare ingredient.
That's an important distinction.
There is enough information to explain why tallow has properties that make sense in a moisturizer.
There is not enough evidence to honestly claim it cures eczema, heals acne, stimulates collagen, reverses aging, or treats skin disease.
And I think consumers deserve to know the difference.
Does Tallow Increase Collagen or Elastin?
This is another claim I see frequently.
Tallow is applied primarily to the surface of the skin.
The main structural proteins we associate with firmness and elasticity — collagen and elastin — are primarily located deeper in the dermis.
There currently isn't good clinical evidence showing that simply applying beef tallow to the skin stimulates meaningful new dermal collagen or elastin production.
That doesn't mean moisturized skin won't look smoother or plumper.
Hydrated, well-conditioned skin reflects light differently and fine dehydration lines can appear less noticeable.
But improving the appearance of dry skin is not the same thing as creating new collagen.
We'll get much deeper into this in another Skin Note.
Is Tallow Non-Comedogenic?
I don't love the way the word "non-comedogenic" gets thrown around in skincare.
Whether a product works for acne-prone skin depends on far more than one ingredient.
Formula composition, amount applied, individual skin biology, cleansing habits, other products, and the type of acne all matter.
Some people with dry or compromised skin love rich balms.
Someone else may prefer something lighter.
There isn't strong clinical evidence that allows us to say every tallow product is universally non-comedogenic.
So I don't.
What I Think Tallow Does Really Well
This is where I personally think tallow shines:
It makes an incredibly rich emollient base.
It can leave dry skin feeling softer, smoother, and more comfortable.
It allows me to formulate concentrated, waterless skincare without creating an ingredient list a mile long.
And when it's combined thoughtfully with ingredients like jojoba oil and vitamin E, I can create a balm that feels beautiful on the skin while staying intentionally simple.
That's why I use it.
Not because I think tallow is a miracle ingredient.
Because I think it's a really good one.
The Twin Tallow Approach
I'm an esthetician first.
I love skincare, but I also think this industry has become unnecessarily complicated.
We don't need to make an ingredient sound magical to appreciate what it does well.
And we don't need to scare people away from every ingredient we don't use.
For me, good skincare starts with understanding the skin barrier, respecting it, and choosing ingredients intentionally.
Tallow is one of those ingredients.
Rich in naturally occurring fatty acids. Beautifully emollient. Intentionally simple.
And that's enough.
Skin Note
Tallow can help moisturize and condition your skin. Your skin itself does the healing, rebuilding, and regulating.
Understanding that difference is exactly what Skin Notes is about.