What Stress Actually Does to Your Skin (Cortisol Face Explained)

Everybody wants to treat the face. Almost nobody wants to treat the reason.

I understand it, because the face is what you can see, and a serum is something you can buy on a Tuesday evening when you are too tired to do anything harder. But if your skin has changed over a difficult year, no amount of active ingredients is going to outrun the thing that changed it. What they will do is give you something to control while everything else feels uncontrollable, which is not nothing, and is also not the answer.

So let's talk about what stress genuinely does to skin. Some of it is more significant than people realise. And the bit that has gone viral is the bit that is mostly wrong.

What cortisol actually does to skin

This is the real list, and it is more substantial than the internet version.

It reduces collagen. Cortisol lowers the rate at which skin produces new collagen and increases the rate at which existing collagen is broken down. Both directions at once. Over months and years of sustained stress, that produces skin that is thinner and less resilient than it was, and it is one of the reasons a hard year genuinely shows on a face.

It damages the skin barrier. Your barrier is the outermost layer, the part that keeps water in and irritants out. Cortisol impairs how well it holds together and slows how quickly it repairs itself after damage. This has been measured directly in studies of people under exam stress and other sustained pressure, and the effect is not subtle.

It slows healing. Spots take longer to clear. Small scratches linger. Anything you do to your skin, including treatments, takes longer to recover from.

It increases oil production. There are receptors on the oil glands that respond to stress-related messengers, and stress also raises androgen activity. This is why adult acne so reliably appears in the month of the deadline, and why it usually turns up along the jaw and chin.

It makes inflammatory skin conditions worse. Eczema, psoriasis and rosacea all flare under stress, and this is one of the best-documented connections in dermatology. If you have one of these, stress is not a vague aggravating factor. It is a trigger with a clear route.

It costs you sleep, and sleep is when repair happens. Most of the skin's overnight repair work happens during deep sleep. A chronically shortened night is a chronically shortened repair window, and the visible result is dullness, poorer texture, and darker under-eyes.

"Cortisol face": what it is and what it mostly is not

Here is the part where I disappoint the algorithm.

There is a genuine clinical sign of very high cortisol that affects the face. It is called moon face, it produces a rounded, full appearance across the cheeks and jaw, and it belongs to Cushing's syndrome. Cushing's is rare, affecting roughly 10 to 15 people per million per year, and it does not arrive alone. It comes with purple stretch marks, skin that bruises at the slightest knock, noticeable muscle weakness in the thighs and upper arms, and raised blood pressure.

If you have facial puffiness and none of that, what you almost certainly have is fluid retention. Which is real, and visible, and useful to understand, but is not the same thing at all.

Common causes of the puffy face people are photographing and labelling as cortisol: salt the night before, alcohol, a short night's sleep, sleeping flat rather than slightly elevated, the second half of your menstrual cycle, crying, hay fever and other allergies, and an underactive thyroid. That last one deserves a mention, because facial puffiness is a recognised feature of hypothyroidism and it is far more common in women in their forties than Cushing's syndrome will ever be.

None of that means stress is irrelevant to how your face looks. Stress affects sleep, sleep affects fluid, alcohol often increases when stress does, and the whole thing joins up. It just does not join up in the way the videos suggest, and chasing "cortisol face" as a diagnosis usually means missing a thyroid test that would have been more useful.

Related reading: If you want the fuller version of which high cortisol signs are real and which are noise, including when to ask for testing: Signs of High Cortisol in Women: What's Real, What Isn't.

Why stressed skin reacts to things it used to tolerate

This is the complaint I hear most often, and it confuses people because nothing in the routine has changed.

The retinoid you have used for two years suddenly stings. The cleanser that was fine now leaves your skin tight. A product you have repurchased four times now seems to break you out.

The products have not changed. Your barrier has. A barrier that is not holding together properly lets more of everything through, including the actives that were perfectly comfortable when it was intact. The skin is not becoming allergic to your routine. It is temporarily less able to cope with it.

The instinct at this point is to add something soothing. The better move is almost always to take things away. Fewer actives, a plain moisturiser, a gentle cleanser, and sun protection, for two to three weeks. Skin that is given nothing to react to usually calms down on its own, and then you can bring the actives back one at a time.

Adding a tenth product to fix the problem caused by the other nine is a very human response and it has never once worked.

What supports skin through a hard month:

The repair window you are giving away

I want to make a specific case for sleep here, because it is the intervention people take least seriously and it does the most.

Skin cell turnover and repair activity are highest during the night, concentrated in deep sleep. Blood flow to the skin increases. The barrier does its rebuilding then. Growth hormone, which supports tissue repair, is released mainly in the first few hours of sleep.

Cut that short, repeatedly, and you are not just tired. You are running a repair process at partial capacity, every night, while continuing to expose your skin to sun, pollution, actives and stress during the day. The gap between damage and repair widens quietly, over months, and then one morning you notice.

A £65 cream applied on five hours of sleep is doing considerably less than the same cream applied on seven and a half. That is not a marketing line and it is a slightly annoying thing to be told, but it happens to be true.

What to actually do when you are under pressure

Take products away rather than adding them. Two to three weeks of the simplest possible routine while your barrier recovers. This is free and it works.

Keep the sunscreen. Whatever else comes out, this stays. Compromised skin is more vulnerable to ultraviolet damage, not less.

Protect the first half of the night. If you cannot get eight hours, get the first four undisturbed. That is where the deepest repair sits.

Do not book an aggressive treatment in a stressful month. Healing is slower and the risk of a poor outcome is higher. I would rather move an appointment than treat skin that is not in a position to recover well from it, and any practitioner who tells you otherwise is thinking about their diary rather than your face.

Deal with the actual stressor, to whatever extent you can. I am aware of how that sounds, and I am aware that most women reading this cannot simply remove the thing causing it. But even partial improvements in sleep, in alcohol, in the amount of unbroken time in a week, change the skin. The skin is not separate from the rest of you. It never has been.

If your skin has changed over a hard year and you want someone to look at the whole of it, internal and external together rather than one at a time, that is what a skin consultation at Debora Tentis Clinic is for. Bring the products you are using. Often the most useful thing I do is tell someone what to stop.

Shop

Keep reading: The practical structure for actually lowering cortisol, rather than treating what it does to your face: Living a Low-Cortisol Life.

Debora Tentis is a Women's Health Pharmacist, Independent Prescriber Trainee and aesthetics practitioner at Debora Tentis Clinic, Milton Keynes. This post is for educational purposes only and does not constitute medical advice.