Do hot showers cause acne? What to know

A hot shower feels good on sore muscles, and plenty of people come out of one with red, tight skin and wonder whether it just made their acne worse.

The answer splits in two. Hot water does something measurable to your skin, and that something is not acne. Both halves are worth knowing, because the advice that follows from them is different.

Skinli gives general education and is not a doctor. Acne that is deep, painful or leaving scars needs a dermatologist.

The AAD says warm, not hot

The temperature advice is already written down, in several places, and it is consistent.

On face washing, the American Academy of Dermatology says to wet your face with lukewarm water, apply cleanser with your fingertips, then rinse with lukewarm water and pat dry with a soft towel. It adds that using a washcloth, mesh sponge, or anything other than your fingertips can irritate your skin, and to resist the temptation to scrub your skin because scrubbing irritates the skin.

On showering after exercise, the AAD's workout page says to consider showering immediately after your work out and to gently rinse it off with warm water. Its guidance on breaking a sweat without causing acne is more direct still: shower immediately using warm, not hot, water.

On dry skin, the AAD advises limiting baths and showers to five to ten minutes, using warm water, and applying moisturizer when your skin is still damp after taking a shower or bath.

Three separate pages, three times the same word. Lukewarm or warm. Never hot.

What hot water actually does, with numbers

The reason behind that advice has been measured.

A 2022 study in the Journal of Clinical Medicine by Herrero-Fernandez and colleagues took 50 healthy people and tested water exposure on their skin. One test was 10 minutes of immersion in hot water, averaging 41.29 degrees Celsius, and in cold water, averaging 11.13 degrees Celsius. The researchers measured water loss through the skin, hydration of the outer skin layer, skin pH and redness.

After 10 minutes	Water loss through skin	Skin pH	Redness
Before	25.75	6.33	249.45
Hot water, 41°C	58.58	6.65	286.34
Cold water, 11°C	34.96	6.62	no rise reported

Water loss is in grams per hour per square metre, and redness in the study's own units.

Hot water more than doubled water loss through the skin. Cold water raised it too, by less. The authors concluded that long and continuous water exposure damages skin barrier function, with hot water being even more harmful, and recommended using cold or lukewarm water for handwashing and avoiding hot water.

So the warm-not-hot advice is not a guess. The barrier measurement moves, and it moves a long way.

Why that is not the same as causing acne

Here is where careful reading matters.

Water loss through the skin is a barrier measurement. It tells you how well the outer layer of skin is holding water in. Acne is something else. The AAD describes acne as developing when pores become clogged, and explains that hormones called androgens increase the size of the skin's oil glands, which then make more oil that can clog pores.

Nothing in the 2022 study measured acne. It measured barrier function, pH and redness on healthy skin. And no dermatology source read for this guide names hot showers, shower water or water temperature as a cause of acne.

So "hot showers cause acne" is a claim nobody read here makes. What is supported is narrower and still useful: hot water weakens the skin barrier, and a weak barrier makes acne harder to treat.

The real problem: hot water plus acne treatment

This is the part that affects whether your skin clears.

Acne treatments are drying by design. Benzoyl peroxide and retinoids such as adapalene both cause dryness and peeling for many people, especially in the first weeks. Skinli's own plan uses adapalene 0.1 percent and benzoyl peroxide 2.5 percent, and expects 8 to 12 weeks of steady use before you judge the result.

Now add a long hot shower. The barrier is already working hard against the treatment, and the hot water raises water loss through the skin on top of that. Skin that stings, flakes and feels tight is skin whose owner stops applying the treatment. That is the actual route from hot showers to worse acne, and it runs through giving up rather than through the pore.

Damaged skin barrier covers the signs to watch for, and how to repair your skin barrier has the steps if yours is already sore.

What the AAD says to avoid in the shower

Temperature is one half. What you do with your hands is the other, and the AAD is blunt about it.

Its back acne guidance says that scrubbing skin with acne may seem best, but this actually worsens acne. It then lists what to keep out: antibacterial soaps, astringents, and abrasive scrubs can worsen acne, and the same goes for loofahs, back brushes and buff puffs. Its recommendation is gentle, fragrance-free skin care products.

A hot shower and a stiff brush tend to arrive together, because hot water makes skin feel like it needs a good scrub. Both are on the list of things to stop. Acne body wash covers which active ingredients belong in the shower instead, and sweat, gym gear and back acne covers the timing around exercise.

A shower routine that fits the advice

Putting the sources together gives something simple.

1. Warm water, not hot. The AAD's word for after a workout, and lukewarm for the face.
2. Five to ten minutes. The AAD's length for dry skin, and the 2022 study found barrier damage at 10 minutes of immersion.
3. Fingertips and a mild cleanser. The AAD says to use a cleanser that is mild and oil free, with a label saying non-comedogenic or will not clog pores. No loofah, no back brush.
4. Shower soon after sweating. The AAD says to shower and change clothes as soon as possible after working out or anything that causes you to sweat. If you cannot, it suggests an oil-free cleansing wipe, or pads containing salicylic acid on skin that tends to break out.
5. Pat dry, then moisturise while damp. The AAD says to gently pat your skin with a clean, dry towel, and to apply moisturizer when your skin is still damp.
6. Clean towel, clean clothes. The AAD says to use a towel that has been washed since you or someone else last used it, and to put on clean workout clothes.

Washing more often is the other instinct that hot showers come with, and it has its own problems. Washing your face too often covers what the AAD says about frequency.

What to tell a shower filter salesperson

Shower filters are sold for acne, so the question deserves a plain answer.

No source read for this guide tested a shower filter, a shower head or water hardness against acne. The AAD acne pages and the NHS acne page do not mention any of them. That is not proof a filter does nothing, and it does mean there is nothing here to justify buying one for acne.

The changes with evidence behind them cost nothing: turn the temperature down, keep it short, stop scrubbing, moisturise while damp.

If your acne is deep, painful, or leaving marks and scars, the NHS advice is to see a GP, including when you have treated it yourself and it is not getting better. Water temperature is not what is driving deep or scarring acne, and it is not what will fix it.