Does Frequent Laser Thin the Skin — What the Studies Show

Three-line summary

• The belief that "laser thins the skin" sits poorly with the evidence. CO2 fractional, nanosecond and picosecond pigment lasers, long-pulsed 1064nm and pulsed dye lasers have all been reported to increase dermal collagen and skin thickness after treatment.
• What actually thins skin is not the laser. It is aging, photoaging, long-term topical steroids, hormonal change after menopause, rapid weight loss and nutritional deficiency.
• Even so, "it feels thinner" is a real experience. It usually comes not from thickness but from barrier disruption, redness and the translucency that appears as pigment clears. And repeat treatment without recovery intervals works in exactly the direction that produces that feeling.

What does "the skin gets thinner" actually refer to?

Many people hold the phrase as a vague bad thing. That impression is not wrong, but strictly it means a decrease in the combined thickness of the epidermis and the dermis. And the changes that follow from it are fairly specific.

• Barrier disruption — water is harder to hold on to, so transepidermal water loss (TEWL) rises, the skin dries out easily and reacts more sharply to outside irritation.
• Loss of firmness, and wrinkles — falling density of the collagen fibre bundles connects directly to more wrinkles.
• Bruising easily — as the tissue that wraps and supports the vessels thins, even small knocks leave bruises.
• Slower wound healing — the same injury takes longer to close.
• Dilated vessels — the skin reaches a state where widened vessels show through readily.

In short, thinner skin means that the capacity to protect and the capacity to regenerate fall together. That is a different story from a face simply looking translucent or showing its colour more easily.

Thickness is not one single block

The skin is built from the epidermis and the dermis stacked in layers, and the two run on different timetables. The epidermis is a layer that has always been made anew and shed from the top. The dermis, by contrast, is a mesh of collagen and elastic fibres that accounts for most of the skin's thickness, and once its density drops it does not come back quickly on its own.

So the "thinning" that matters is mostly a story about the dermis. The epidermis feeling rough for a few days after treatment, or the stratum corneum thinning temporarily, is a different kind of event from a loss of thickness that does not return. Keeping that distinction makes everything below much clearer.

Which leaves one question to check

The precise question is not "does laser thin the skin" but "what is it that decreased?" Whether what decreased is dermal collagen density, a stratum corneum still in recovery, or simply the pigment that was covering the skin, the response changes completely.

What actually thins the skin

The situations in which skin thickness falls are already reasonably well described. Reading the list, the first thing you notice is that laser is not on it.

Aging — around 6.4% per decade on average

A number of papers report that from adulthood onward skin thickness decreases by roughly 6.4% per decade on average, and this change is understood to be linked to a fall in collagen synthesis.

Looking a little closer, epidermal thickness and dermal thickness rise into the twenties and thirties and then decline, with the decline becoming clear from the forties to the sixties in particular. Collagen content likewise starts to fall from the thirties. That is part of the background to the several different lines of treatment developed to supplement collagen or stimulate more of it.

Differences between men and women have also been reported. It is fairly well known that men's skin is thicker than women's, but the rate at which thickness falls is also faster in men. In the figures surveyed, men decreased by about 7.2% per decade and women by about 5.7%. A thicker starting point, then, is not a reason to put skin care off.

Photoaging — the sun you have had, more than the years

Separately from the changes that come with age, photoaging from sun exposure also contributes to the loss of skin thickness. In Western populations there are reports that photoaging drives the decrease in skin thickness more directly.

There is a reason this matters in an actual consultation. While treatment is being postponed out of concern about thickness, UV exposure keeps accumulating every day. In order of priority, sun protection is by far the earlier variable.

Topical steroids — the real cause most often passed over

Long-term application of topical steroids causes atrophy of the epidermis and dermis, reduces elasticity and creates conditions in which bruising happens easily. The mechanism is relatively clear: it interferes with collagen synthesis and elastin production and suppresses fibroblast function.

This is why patients are advised not to keep applying dermatitis ointment indefinitely. The itching settles, so application continues; symptoms return, so it goes on again — and months or years pass this way more often than you would think. When someone tells us in clinic that their skin has become thinner, the item we check before any laser history is how long the ointment was used.

Hormones and body weight — whole-body change leaves its mark on the skin

• Falling oestrogen after menopause — known to reduce skin thickness and collagen content markedly, reported at around 1.13% per year.
• Nutritional deficiency — thins the skin. When the raw material to build with is short, maintenance becomes difficult too.
• Rapid weight loss — when BMI falls, skin thickness has been reported to fall along with it.

When a period of weight loss overlaps with a course of treatment it is easy to point at the laser, but the two are different variables. To put it together: people past their thirties, people with heavy sun exposure, men, women after menopause and people in the middle of rapid weight loss are the groups for whom loss of skin thickness needs relatively more attention.

So how did laser end up on this list?

The causes above share something. They all progress slowly and without drawing attention. Aging does not start on a particular day, and neither does hormonal change or ointment use. So when someone feels at some point that their skin has changed, they name as the cause the most conspicuous event that happened around that time.

Laser is an event with a date on it. You know when you had it, and for a few days afterwards the skin really does look different from usual. Years of UV exposure and a long-used ointment carry no date. It is natural that the memorable one gets named as the cause, but that is a different thing from how much it contributed. This is also why the belief survives so long.

What the papers actually show about lasers

Set against the clinical and histologic evidence, the idea that lasers and energy-based devices thin the skin looks closer to a belief with little support. Most of these devices have instead been reported in connection with collagen production, dermal thickness and elasticity increasing in the skin. Let us take them by type.

CO2 fractional — the laser that looks most like "sanding"

Even its name suggests a treatment that works on the surface, so it draws the most misunderstanding. Yet the findings pointed the other way. Studies that measured skin thickness with ultrasound before and after fractional treatment found an increase, and studies carried out with biopsies also found skin thickness increased.

So CO2 fractional is less a treatment that thins the skin than one that leans toward thickening the dermis. At ABLE Dermatology we use CO2 fractional when working on pores, scars and skin texture, and the CO2 laser when removing lesions one point at a time, such as moles or age spots.

Nanosecond Q-switched 1064nm Nd:YAG

This is the family most widely used for toning. Research was carried out on its effect on wrinkles at a time when there were fewer ways to improve collagen than there are now, and there is a report that dermal thickness increased when assessed by biopsy three months apart, before and after treatment. That said, the degree is described as smaller than with ablative lasers such as CO2 fractional, which also work on the surface.

Goldberg DJ, Silapunt S. Histologic evaluation of a Q-switched Nd:YAG laser in the nonablative treatment of wrinkles. Dermatol Surg. 2001 Aug;27(8):744-6.

At ABLE Dermatology, Spectra is the device we run in this family. The difference between nanosecond and picosecond, and the criteria for choosing toning as an approach at all, are covered in a separate column, so here we take only the part about thickness.

Picosecond lasers

Picosecond lasers divide into toning mode and fractional mode (MLA). There are reports of collagen regeneration in toning mode as well, confirming movement in the direction of thicker skin, and with the picosecond fractional mode used for pores and scars, dermal collagen was found to increase up to 28 days after treatment.

Han HS, Hong JK, Park SJ, Park BC, Park KY. A Randomized, Prospective, Split-Face Pilot Study to Evaluate the Safety and Efficacy of 532-nm and 1,064-nm Picosecond-Domain Neodymium:Yttrium-Aluminum-Garnet Lasers Using a Diffractive Optical Element for Non-Ablative Skin Rejuvenation: Clinical and Histological Evaluation. Ann Dermatol. 2023 Feb;35(1):23-31.

You can read it as working to build collagen at the same time as it treats melasma or scars. At ABLE Dermatology we run both toning and fractional modes on PicoPlus.

Long-pulsed 1064nm Nd:YAG

This family is used for both pigment and redness, and delivering this wavelength repeatedly at low intensity is commonly called Genesis. The name itself comes from collagenesis. There are indeed reports of collagen in the skin increasing with this family as well.

At ABLE Dermatology we use this wavelength for Gold PTT and Genesis toning. It is the approach we choose when the dermal environment needs improving at the same time.

Pulsed dye laser (PDL) — and here comes an important clue

V-Beam, known as the vascular laser, belongs to this family. In the early 2000s several studies found that PDL induced collagen production in the dermis, and some confirmed the increase in collagen on ultrasound imaging.

But there is a detail here worth noting. Some studies reported skin thickness decreasing temporarily after vascular laser treatment and then returning to normal. The final result was not a conclusion that skin thins, but it does mean such a window exists in between. This is exactly where it meets the "it feels thinner" experience we come to next.

Ultrasound, radiofrequency and other energy-based devices

A good number of energy-based devices that are not lasers were designed from the outset for collagen regeneration and anti-aging. Various studies report a significant increase in collagen density, structural thickening extending down to the fascial (SMAS) layer, and sustained collagen synthesis over the longer term. These sit on the side of treatments that thicken rather than thin.

The epidermis and the dermis change in different directions

The reason the belief survives even though the findings point consistently one way is that the moment a laser meets the skin and what happens afterwards look like two different things.

Ablative and non-ablative — treating the epidermis, or leaving it in place

• Ablative — CO2 fractional and the CO2 laser belong here. They create very fine columns of injury in the epidermis and upper dermis and let the healthy tissue left between them lead the recovery. Judged on the visible moment alone it is a treatment that removes tissue, but new collagen is built in the process of filling those columns in.
• Non-ablative — most pigment and vascular lasers sit here. They preserve the epidermis and either stimulate its upper layers finely or pass through it to deliver heat into the dermis. Because nothing is removed from the surface, the explanation that it "sands the skin thin" does not hold in the first place.

Both approaches end up heading to the same place: improving the dermal environment and building collagen. What differs is the route there and the time recovery needs.

The epidermis is replaced, not subtracted

The epidermis is a layer that cycles by nature, with new cells forming below and old ones shed above. The stratum corneum feeling thin and rough for a few days after treatment is that cycle brought forward all at once, not a decrease that sets in place.

What matters is what comes next. Given enough recovery time, the epidermis returns to its original structure. If a further stimulus reaches the same area before recovery has finished, on the other hand, that layer stays in an unfinished state. This is the most important fork in this article. The problem arises not from the laser itself but from the time between one laser and the next.

The dermis responds to stimulus by building

When microscopic injury or heat reaches the dermis, fibroblasts are activated and new collagen is laid down along the wound-healing response. What the studies above showed is the outcome of exactly this process.

That response does not grow without limit in proportion to the number of times you stimulate it, though, because dermal remodeling proceeds not during the stimulus but during the recovery period that follows it. Pile up stimulus without allowing time to recover and what accumulates moves closer to inflammation than to collagen.

So why does it feel thinner?

This experience is not to be dismissed. It is said because something genuinely does look different in the mirror, and the observation itself is usually accurate. It is just that what was observed is often not thickness.

① Barrier disruption — the most common thing behind the feeling

Stinging, tightness, makeup sitting badly, flushing at the smallest provocation. In everyday language that bundle of sensations is translated almost without exception as "my skin has got thinner." But this is a matter of the stratum corneum and the skin barrier, not of dermal thickness.

The barrier is a layer that can recover. Reduce the irritation, secure time to heal, and the tightness and stinging tend to settle with it. Conversely, this state drags on when treatment continues without recovery intervals, or when aftercare was too harsh.

② Vessels showing through more clearly

When skin genuinely thins, vessels show through. So people reason backwards: if vessels are visible, it must have thinned.

But several things besides thickness make vessels stand out. Temporary vessel dilation after treatment, the erythema left where inflammation has passed, and the state of an epidermis still recovering all produce redness with no change in thickness. The PDL studies noted earlier, where thickness fell temporarily and then recovered, connect here too. It means one frame from the recovery window is easily mistaken for the final state.

③ The translucency that comes as pigment clears

When pigment treatment goes well, tone brightens and evens out. As it does, the faint shading that had been covering the skin lifts, and the colour and texture beneath show more distinctly than before. Many people describe this change as "my skin looks thinner" or "it has become translucent."

What decreased here is not thickness but the pigment that was covering it. In most cases it is the result of treatment going as intended. Continuing the same treatment after the lesions you set out to treat have already cleared is an entirely different matter, though, and that is the subject of the next section.

④ The time gap between the recovery window and the final result

Dermal remodeling proceeds over several months. The few weeks right after treatment, meanwhile, are the window in which skin is most sensitive and most red. If the impression formed in that period sets, it leads easily to the conclusion that "the laser ruined my skin."

That is why we describe in advance what the recovery window will look like. Knowing what you are going to see makes the same scene read differently, and it cuts down decisions to rush the next session or stop unnecessarily.

How to tell thinner apart from looking thinner

In clinic we generally check in the following order. These are items you can also weigh up at home to gauge which side you are closer to.

• When it started — if the change began right after a particular treatment, a recovery window is likely; if it came on gradually over several years, we look first at the causes set out in the earlier section.
• Whether you bruise easily — where thickness has genuinely decreased, a tendency to bruise from small knocks tends to appear alongside it. If the skin is only red and sensitive and bruising is no different from usual, the barrier is the more likely explanation.
• How fast wounds heal — thickness and regenerative capacity generally move together. If small wounds close at much the same speed as before, it is hard to read the regenerative capacity itself as reduced.
• Which area is affected — a change confined to the treated area is likely part of recovery; if untreated areas and the body have changed too, we look for a systemic cause.
• Whether it returns with time — a change that recovers when irritation is reduced and a few weeks are allowed to pass is on the barrier and redness side. Dermal thickness does not come and go over so short a span.

This distinction matters because the response to the two situations differs. If it is a barrier and redness problem, what is needed is time to recover and care that reduces irritation; if thickness has genuinely fallen, the contributing factor has to be dealt with first. Either way the starting point for a judgement is identifying the cause, not drawing a conclusion from whether treatment was had.

So where does repetition become a problem?

It would be a problem if everything so far were read as "lasers are safe, so you can have plenty of them." What the studies showed is that dermal collagen and skin thickness were reported to increase when treatment was carried out at appropriate intervals and energies. It is a conclusion with a condition attached, and that condition is what produces the result. Trouble generally arises at four points.

① When there is no recovery interval

Excessively frequent treatment and excessive energy on the same area have to be avoided. The intervals clinics commonly advise — for instance the three to four weeks for toning or fractional treatment — are a range set on the basis of studies and clinical experience.

The request we meet most often in clinic is "I want to finish sooner, so please shorten the interval." But when a further stimulus arrives before the epidermis and the barrier have been repaired, what accumulates is not results but inflammation. And that state produces exactly the "feeling of thinness" set out in the previous section. Shortening the interval, in other words, is the fastest route to turning the belief into reality.

Nor does the figure of three to four weeks mean the same thing for everyone. Recovery speed differs between individuals, so if redness or flaking is still present it is better to go by the condition of the skin than by the calendar.

② When it is repeated without an indication

There are cases where the same treatment continues under the name of "maintenance" even though no lesion is left to treat. What is gained then is small, while the burden the skin carries stays the same.

Repetition that has lost its target easily becomes a matter of filling in sessions. Pigment treatment in particular tends to pull toward continuing the better the course goes, which is why deciding at the start when you will stop matters. Agreeing in advance on the point at which the interval lengthens or the course ends makes the judgement far easier.

③ When energy is raised to go faster

Expecting that going harder will make things improve sooner is natural. But raising energy also lengthens the time recovery needs, and raises the likelihood of post-inflammatory hyperpigmentation or lasting redness along with it.

Pigmented lesions in particular can respond less predictably the stronger the stimulus. So keeping to a planned interval at an appropriate intensity tends to give a steadier course than raising intensity to reduce the number of sessions. Responses differ between individuals.

④ When the skin is already at a disadvantage

If any of the real causes set out earlier is currently in play, the picture changes.

• Where topical steroids have been used long term — skin in which atrophy has already progressed recovers more slowly from the same treatment.
• Where rapid weight loss is under way — this is a period in which the whole body has less capacity to recover.
• Around menopause — a window in which hormonal change reduces thickness and collagen together.
• Where the barrier is badly disrupted — redness and sensitivity after treatment last longer than usual.

What creates the problem in these cases is not that the laser reduces thickness but that the capacity to recover is reduced. So it is better to change the order. Stabilise the barrier and the redness first and place the laser afterwards, and the same treatment recovers more easily and the result follows more reliably.

Four things to check, in short

• Interval — set the next session by how far the skin has recovered, not by the calendar.
• Indication — you should be able to say what this session is treating.
• Energy — check whether intensity is being raised for the sake of speed.
• Condition — look first at ointment use, weight change, hormonal status and the state of the barrier.

How ABLE Dermatology plans a course of laser treatment

The lasers we run at ABLE Dermatology are PicoPlus (picosecond Nd:YAG — toning and fractional), Spectra (nanosecond Q-switched Nd:YAG), CO2 fractional and the CO2 laser, V-Beam (pulsed dye 595nm), and Gold PTT and Genesis toning, which use long-pulsed 1064nm. Alongside these we run PDT for treatment-resistant acne and LDM for calming and barrier recovery.

More gets decided before the device is chosen than in choosing it.

• If thickness is the concern, we do not start from the laser history — we check first how long topical steroids were used, any recent change in weight, the level of sun exposure and whether menopause is near. That is where the variables that act strongly on thickness actually sit.
• We settle the target lesion before the number of sessions — deciding which lesion to treat and how far also settles when to stop.
• Intervals are adjusted by looking at the skin — if redness or flaking remains, we put the next session back. The same three to four weeks means different things to different people.
• If the barrier and redness are unstable, we change the order — stabilisation first, laser second. The more urgent a situation looks, the more this order decides the result.
• We do not use intensity to go faster — instead of raising energy to finish sooner, we keep to the interval we planned.
• We say in advance when we will stop — once the target lesions have cleared, we lengthen the maintenance cycle or end the course.

There is no need to postpone treatment you need out of worry that laser will thin your skin. At the same time, safe does not mean unlimited. The conclusion the studies produced carries the condition of appropriate intervals and energies, and keeping to that condition is most of what actual practice consists of. Results and recovery speed differ between individuals.

From consultation through to treatment

A board-certified dermatologist examines you directly, identifies which layer the cause sits in, decides the device and the parameters, and then the same dermatologist carries out the treatment. There is no structure in which a consultant recommends procedures.

The number of sessions, the intervals, when maintenance starts and the cost are all agreed together before the first treatment.