Why Laser Hair Removal May Not Work on Gray or White Hair

Why gray and white hair defeat the laser's mechanism

The laser will not clear a field of white hair, and it is an unreliable tool for hair that has lost most of its pigment. Hairs that are still dark can absorb the light and may thin. Hairs that are gray or white give the laser little or nothing to absorb, so they are the hairs most likely to remain. A six-session package buys treatment of the dark hairs. It does not buy removal of the white ones.

Laser hair removal is built on selective photothermolysis. In a 2020 review of laser treatment for hirsutism, Bhat and colleagues describe it this way: selective thermal damage occurs when enough energy is delivered at a wavelength the target absorbs, within a time at or below the target's thermal relaxation time. For hair, they name the target directly: melanin in the hair bulb and bulge. The American Academy of Dermatology puts the same idea in patient language: the laser emits a beam of light, which the pigment in the hair absorbs, and over time that can destroy the follicle so the hair cannot grow back.

A representative professional clearance says the same thing in device language. The 510(k) summary for K241860, a diode laser hair-removal system cleared on September 25, 2024, states that the 808 nm light is preferentially absorbed by the melanin of the hair and converted to heat. That sentence describes the mechanism. It is not a promise about gray or white hair.

American Academy of Dermatology: "Laser hair removal won't work on blonde, white, gray, or red hair because lasers cannot effectively target light-colored hair."

Mayo Clinic: "The treatment is most effective when there is a clear contrast between hair color and skin color, such as black hair and white skin. The laser targets pigment in the hair. So darker hair usually responds best. Blonde, white and gray hair have less pigment. So the treatment is less effective. It also doesn't work as well on red hair. Red hair contains a different type of melanin that doesn't absorb enough laser energy to damage the hair follicles."

Those two pages are not identical, and the difference matters. Mayo Clinic says blonde, white, and gray hair have less pigment, so treatment is less effective, and that red hair contains a melanin that does not absorb enough energy. The Academy's everyday-care page draws a harder practical line: the laser will not work on blonde, white, gray, or red hair. Neither page is a trial of a particular device. Together they tell a person with white hair not to expect a laser series to finish the job.

The Academy's laser hair removal FAQ adds a sentence that is easy to misuse. It says that today laser hair removal is a treatment option for patients who have light-colored hair and light skin, and for patients who have dark skin, when it is performed very carefully. The same FAQ says laser hair removal works best for light-colored skin and dark-colored hair, and that most patients need 2 to 6 treatments, with about a 10% to 25% reduction after the first one. That FAQ is about who can be treated when some pigment is still there and the operator is careful. It does not say a white hair has a melanin target. Light brown hair, and some hair that looks fair, can still hold eumelanin. White hair, in the histology below, is a different biological object.

One more Academy limit belongs in this decision because the scenario includes the chin. On the same everyday-care page, the Academy says that after 6 or more treatments to an area, laser hair removal is permanent, except on a woman's face, and that it takes about 6 treatments from a dermatologist to destroy a follicle the laser can target. That permanence wording applies to hair the laser can see. It does not cancel the statement that blonde, white, gray, and red hair are not effective targets. Dark chin hair on a woman sits under the facial exception even when the pigment is still there. White chin hair sits under the color limit.

What gray actually is: pigment lost inside the follicle

Gray hair is not a laser setting problem. It is a loss of the cells that make pigment inside the follicle, which is why dyeing the shaft does not create a target.

Commo, Gaillard, and Bernard examined human follicles across stages of whitening and published the work in the British Journal of Dermatology in 2004. Loss of hair-shaft melanin tracked with a decrease in both bulb melanin and the bulb melanocyte population. Gray bulbs still contained a few melanocytes. Those cells still expressed tyrosinase and tyrosinase-related protein-1 and still transferred some melanin to cortical keratinocytes. In white hair bulbs, no melanocytes were detected with the markers they used. Outer-root-sheath melanocytes, the inactive reservoir along the follicle, were also reduced, from a small population down to none. The depletion was specific to melanocytes: other outer-root-sheath cells, including putative stem cells, Merkel cells, and Langerhans cells, were still present. Their conclusion was direct: hair greying appears to be a consequence of an overall and specific depletion of bulb and outer-root-sheath melanocytes.

That split is the reason a salt-and-pepper area is not the same decision as a fully white one. A gray follicle in this study was depleted rather than empty, so some melanin can still be present. That histology study did not measure whether the remainder is enough for a laser to heat the follicle. A white follicle in this study had no detectable bulb melanocytes, so there was no melanin target left to heat. An unreliable gray hair is not a reason to prepay for a field of white hair.

O'Sullivan and colleagues, writing in Biological Reviews in 2021, place the start of human graying in the anagen hair bulb. Graying invariably begins with a gradual decline in melanogenesis, including reduced tyrosinase activity, defective melanosome transfer, and apoptosis of melanocytes in the hair-follicle pigmentary unit. The bulge melanocyte stem-cell pool is depleted later, and at that stage graying is largely irreversible. Oxidative damage is, in their reading, a likely driver. The review is biology, not a treatment manual. It explains why the missing chromophore is inside the follicle from the time the shaft is made, rather than a stain that sits only on the hair you can see.

What regulators have cleared — and what they have not

Clinic language often slides from "cleared for all skin types" to "works on all hair." The U.S. records below do not make that slide. A 510(k) clearance is a finding of substantial equivalence to an already marketed device. It is not a drug-style approval, and it is not a new clinical trial unless the summary says one was done.

The indications for use in the K241860 summary read: "The Diode Laser Hair Removal System is intended for hair removal, permanent hair reduction on all skin types (Fitzpatrick skin type I-VI), including tanned skin. Permanent hair reduction is defined as the long-term, stable reduction in the number of hairs regrowing when measured at 6, 9, and 12 months after the completion of a treatment regime." The device is Class II, product code GEX, under 21 CFR 878.4810. Under clinical testing, the summary states: "No clinical study is included in this submission." The same PDF's device description uses promotional phrasing, including a claim of permanent hair removal. The governing sentences are the indication, which names skin types and a 6-, 9-, and 12-month reduction definition, and the statement that no clinical study was included. The indication does not name gray, white, blonde, or red hair.

K241860 is one 2024 diode clearance, useful because its wording is typical of this class, not because it is a census of every laser on the market. In the records assembled for this article, professional clearances of this kind cover Fitzpatrick skin types. They do not add a permanent-reduction claim for hair that lacks melanin.

At-home light-based hair removal sits in the same regulation. Product code OHT is Class 2, 510(k), 21 CFR 878.4810. The FDA classification database defines it as an over-the-counter device that uses thermal energy to kill hair follicles for hair removal. That page does not list a hair color, and it does not say the category is indicated for white, gray, or blonde hair. The Academy says at-home laser devices take a lot longer to show results and have to be used periodically to maintain them, and that these devices are not for everyone. A lower-power version of the same thermal idea does not create a chromophore the professional laser lacks.

The clearance in this review that does name gray and white hair is SNA-001 Silver Photoparticle Topical Gel, K192620. The FDA database lists the applicant as Sienna Biopharmaceuticals, Inc., product code QCY with subsequent product code GEX, regulation 878.4810, and a substantially equivalent decision on August 12, 2020. The clinical-trial field on that record is NCT02870959. The 510(k) summary lists Sebacia, Inc. as the submitter and gives the indication in full: SNA-001 is indicated as an accessory to an 810 nm diode laser for temporary removal of light-colored hair in patients with skin types I, II, and III. Light-colored hair types include blonde, light red, light brown, gray, and white.

Two limits in that sentence do most of the work. The claim is temporary removal, not the 6-, 9-, and 12-month permanent-reduction definition used for K241860. The skin-type limit is I through III only. The summary also identifies the predicate as ThermoLase Softlight Carbon Lotion (K971207), an earlier particle lotion used as an external chromophore with a Q-switched 1064 nm laser. SNA-001 is the silver-particle clearance that names gray and white hair. It is not evidence that a bare diode, alexandrite, Nd:YAG, or home IPL is cleared to permanently reduce non-pigmented hair.

Read the last row's "FDA-approved" cell as Cleveland Clinic's wording, not as a second 510(k) indication. Laser hair-removal devices in the table are cleared, under 510(k), for a defined reduction in regrowing hairs. The archived FDA page says electrolysis is considered permanent because the follicle is destroyed. Those are different claims. A clinic that says its laser is "FDA approved for permanent removal of white hair" is joining phrases the clearances above do not join.

The research on making light hair treatable — and why it stalled

If the follicle will not supply melanin, investigators have tried to bring in another absorber, or to add energy that does not depend on pigment. The studies are real. The results are small, and none of them became a cleared claim of permanent reduction for gray or white hair.

Liposomal melanin: the Sand 2007 trial

Sand and colleagues tested whether an external melanin could stand in for the missing pigment. The indexed paper is in Annals of Plastic Surgery, 2007, volume 58, pages 551–554. The spray in the trial was Lipoxome, a liposomal melanin from Dalton Medicare. Meladine is a different topical name, and it is not the product this trial tested.

The abstract describes 42 areas of blond, gray, or white facial and body hair in 16 patients, treated with Lipoxome and three cycles of an 800 nm diode laser at eight-week intervals, at fluences of 28–40 J/cm². Those fluences are the trial conditions, not a setting to copy. A control group of 16 patients used physiological saline before diode treatment. Mean regrowth in the liposomal group was 83% after three cycles. Six months after therapy, terminal hair counts were 14% below baseline in the liposomal group and 10% below baseline in the saline group. The difference was statistically significant (P < 0.05). The authors still called the clinical outcome disappointing, and they wrote that the weak reduction plus the extra effort and cost argued against the formulation.

The 83% figure and the 14% figure are different time points. After three cycles, most of the hair had regrown. At six months, the liposomal side was only a few percentage points ahead of saline. A statistically significant gap of that size is not a cleared treatment and not a reason to buy a melanin spray before a laser package.

Bhat's review mentions Meladine as a topical melanin chromophore studied in Europe, in a sentence separate from its citation of Sand's liposomes. The review does not report a permanent-reduction number for Meladine. Treat that name as a different external-chromophore idea, not as the product in the Sand trial.

Optical and radiofrequency energy: the Goldberg 2005 study

Goldberg, Marmur, and Hussain tested a combined pulsed-light and bipolar radiofrequency device, with and without topical aminolevulinic acid, and published the study in the Journal of Cosmetic and Laser Therapy in 2005, volume 7, pages 25–28. Fifteen women with skin types II–IV were treated twice, four to six weeks apart. Ten had white terminal hairs. Five had fine facial vellus hairs. At each visit, half the area was pretreated with aminolevulinic acid.

At six months, average removal of terminal white hair was 35% with the combined device alone and 48% on the side pretreated with aminolevulinic acid. None of the five women with vellus hair responded to either side. The authors' conclusion says combined radiofrequency and optical light leads to effective hair removal of terminal white hairs, and that aminolevulinic acid increased that improvement. The counts are still a partial reduction: most terminal white hairs were present at six months, vellus hairs did not respond, and the terminal-hair sample was 10 women treated twice. Bhat's review calls this line of work "some success." It is not a 510(k) claim of permanent reduction for white hair, and the device is not the thing a med-spa package is usually selling.

SNA-001: what the 510(k) summary showed

The efficacy numbers that circulate for SNA-001 come from a company announcement. Dermatology Times reported that announcement in February 2019: after six treatments in 65 patients, hair decreased an average of 17.5% with SNA-001 plus an 810 nm diode laser, versus 1.1% with vehicle plus laser, and the company described up to about a 32% reduction from baseline. That article is trade coverage of a press release. The 510(k) summary is the record that belongs next to the clearance.

The summary describes a U.S. multicenter, randomized, within-subject controlled study with blinded assessment. Seventy-seven people were treated and counted in the safety population. Sixty-five were in the intent-to-treat population, and 49 were in the per-protocol population. Each person had treatment areas on the left and right of the face (upper lip or posterior neck), the axilla, or the bikini line. Skin types were only I (9.2%), II (61.5%), and III (29.2%). Hair color was mostly light brown (33.8%) or blonde (32.3%). Light red and white hair were each 9.2%. Gray hair was 3.1%. A mixture of light colors was 12.3%. The 17.5% average is not a result in a gray-hair population. Gray hair was a small slice of the sample.

The primary measure was the mean percentage change in hair count from baseline to three months. In the intent-to-treat observed data, the means were −17.5% with SNA-001 plus laser and −1.1% with vehicle plus laser. The summary says the mean reduction was numerically higher with SNA-001 in both the intent-to-treat and per-protocol analyses, and that the mean differences were not statistically significant. Non-inferiority, a preset test of whether SNA-001 plus laser was not worse than vehicle plus laser beyond a chosen margin, was met for the imputed intent-to-treat analysis. That is a narrower statement than "the gel clearly outperformed laser alone."

In a further cut, the proportion of people who reached at least a 50% hair-count reduction at three months was 17.4% with SNA-001 plus laser and 8.7% with vehicle plus laser (p = 0.046). Other thresholds in that analysis were not statistically significant. Local reactions included erythema, blistering, scabbing, bruising, rash, and one report of pigmentation change. The summary says those events resolved, with no treatment-area events reported at three months and no serious treatment-related events. The cleared indication remained temporary removal in skin types I–III. The summary does not establish that the gel is on the U.S. market now, and it does not support using an 810 nm laser alone on gray or white hair.

No source reviewed for this article is a controlled trial showing permanent reduction of gray or white hair with a long-pulsed Nd:YAG or a combination platform. Bhat still names melanin in the bulb and bulge as the chromophore, and still says absence of melanin often means failure.

Salt-and-pepper hair: the case that deserves a real consultation

Salt-and-pepper hair is a mix of follicles, not a third hair color. A dark follicle beside a white one still holds eumelanin. The laser can heat the dark hair. The white hair, which in Commo's white-bulb specimens had no detectable melanocytes, does not offer that target. Mayo Clinic's contrast rule points the same way: treatment is most effective when hair pigment and skin pigment are easy to tell apart. A white hair on any skin tone is the low-contrast case.

There is a timing consequence. The Academy's FAQ says that when hair regrows after laser treatment, there tends to be less of it, and the hairs tend to be finer and lighter. A course aimed at the dark hairs can shrink that dark share. It can also leave a lighter remainder, which is the hair the same FAQ and the everyday-care page say the laser handles poorly or not at all. Waiting until the beard or the underarm is almost entirely white leaves the laser with little pigment to find. Starting while a substantial share of hairs is still dark can reduce that dark share. It does not recruit the white hairs later.

The 10% to 25% reduction after a first treatment, and the 2 to 6 treatments the FAQ cites, are figures for patients who are actually candidates, in a page that says the best case is light skin and dark hair. They are not a forecast for the white hairs in a salt-and-pepper field. Bhat's review, which is about hirsutism rather than canities, says a single laser treatment can reduce hair by 10% to 40% and repeated treatments by as much as 90%, with results that may persist as long as 12 months, and also says lasers do not provide permanent hair removal. Those ranges describe pigmented-hair laser treatment in the studies the review pooled. They are not white-hair rates, and they should not be quoted as what a gray chin will do.

What to ask before you pay

Take the questions. Leave if the answers treat white hair as a settings problem.

• What share of this area is still dark? Ask the clinician to look at the chin and the underarms and say, in ordinary language, how much of the hair is dark enough to treat and how much is gray or white. A package sold without that look is a package sold to an average patient you may not be.

• Will they say that white, gray, blonde, and red hairs are not laser targets? The Academy's everyday-care page says the laser will not work on those colors. A claim that a "new" device treats all hair colors needs a clearance or a trial of the kind in the tables above. A brochure is not that record.

• Will they raise the energy to chase white hairs? Extra fluence does not put melanin into an empty bulb. On skin that already holds melanin, it raises the chance that the skin takes the heat. Mayo Clinic says uncommon effects include blistering, crusting, scarring, and changes in skin texture.

• Is there a test spot before the package? Ask whether a small area is treated and observed before you buy a series. Do not accept a verbal "everyone tolerates it."

• What happens to unused sessions? If the dark hairs clear and the white hairs remain, can the balance be refunded or moved, or is it gone? The discount that expires this week is not a reason to fund hairs the device cannot see.

Alternatives that do not depend on pigment

When the hair no longer supplies a chromophore, the methods that still make sense are the ones that do not need one.

Electrolysis: the method that does not need melanin

The archived FDA consumer update, a 2019 snapshot of a page whose content was current as of June 30, 2010, says: "Electrolysis is considered a permanent hair removal method, since it destroys the hair follicle. It requires a series of appointments over a period of time." The same page says needle epilators place a fine wire into the follicle and send an electric current that destroys the hair root, and that medical electrolysis devices use a shortwave radio frequency after a thin probe is placed in the follicle. Infection from an unsterile needle and scarring from improper technique are the risks it names. The live fda.gov address for that page now returns an error, so this article cites the archive and the date, not a current FDA webpage.

Cleveland Clinic says electrolysis is the only FDA-approved method for permanent hair removal, that a trained electrologist uses an electric current, and that it works with the widest range of skin and hair types. Appointments are typically every week or every other week and can continue for up to a year and a half. Coarse hair and larger areas need more treatments. The clinic calls the procedure very safe, with a slight risk of infection from an unsterile needle or scarring if it is done incorrectly, and notes that people with darker skin may have temporary dark spots.

The Academy says electrolysis sends an electrical current through the follicle, takes several sessions because hair grows in cycles, and can permanently remove unwanted hair, including light-colored hairs lasers cannot remove. It also says unsterile probes can cause a skin or blood infection, inexperienced hands can cause scarring and burns, and people with darker skin tones can develop a keloid. Home electrolysis kits, the Academy notes, do not insert probes the way professional treatment does. The FDA update adds that tweezer devices, which grasp the hair and apply energy at the tweezer tip, do not have a body of significant information establishing permanent removal.

"FDA-approved," in the Cleveland Clinic sentence, should stay attached to that sentence. It is not the same regulatory act as the 510(k) clearances in the table. Those laser clearances use "permanent hair reduction" and define it at 6, 9, and 12 months. Electrolysis, in the FDA consumer wording, is considered permanent because the follicle is destroyed. Hair color does not supply the target, which is why white and gray hairs are in scope for electrolysis in a way they are not for a bare laser. That does not mean every hair caliber clears at the same speed. Cleveland Clinic says coarse hair needs more visits. The Academy's keloid warning is a reason to choose a board-certified dermatologist or board-certified electrologist, which is the operator the Academy names, and to treat darker skin as a scarring concern rather than as a footnote.

Temporary methods, if you do not want electrolysis

Shaving, waxing, and depilatories do not destroy the follicle. They also do not care what color the hair is.

• Shaving. The Academy says a razor cuts hair at the skin surface and that results are short-lived, sometimes daily or every few days. The archived FDA page says shaving does not change the texture, color, or growth rate of hair. Cuts, razor burn, and ingrown hairs are the ordinary costs.

• Waxing. The Academy says wax pulls hairs out and that results can last a few weeks or longer. Removing the wax can hurt, the skin can stay red for a short time, and wax that is too hot can burn. Waxing is not a substitute for electrolysis on white hair.

• Depilatories. The FDA update describes them as cosmetic creams, gels, or lotions that affect hair protein so the hair can be wiped away. The Academy says the result tends to last longer than a shave and that the products can irritate skin, so a patch test on the product is worth doing before wider use. They do not create a laser target and they do not destroy the follicle.

If you proceed anyway: money, safety, and skin-of-color cautions

Paying for laser sessions on fully white hair buys the risks of a laser appointment without the mechanism that would justify them. Paying for a salt-and-pepper area can still be rational if the price matches the dark hairs only, and if the operator will not "turn it up" to chase the rest.

Why turning the energy up does not create a target

Selective photothermolysis needs an absorber. White bulbs in the Commo study had no melanocytes to supply one. Raising fluence or shortening the pulse does not manufacture melanin. The energy has to go somewhere. On the skin, the competing absorbers include epidermal melanin.

Mayo Clinic says black and brown skin contain more melanin, so the laser type and the settings matter, and that this choice is part of reducing burns and lasting changes in skin color. It also says laser hair removal can be used on black or brown skin when an experienced professional performs it, and that darker skin's extra melanin is why the laser and the settings have to be chosen carefully. Uncommon effects include blistering, crusting, scarring, and changes in skin texture. Color change is usually temporary and can be lasting in rare cases, with higher risk in people with black or brown skin and in people who do not avoid the sun before or after treatment. The Academy FAQ says laser hair removal can be dangerous in inexperienced hands, and that burns, permanent changes in skin color, and scars can occur.

Thicker regrowth, eyes, and tattoos

Mayo Clinic says that, rarely, hair may grow thicker in the area around the treated skin. That is a reason to stop a series that is not clearing the hair it was sold to clear, not a reason to keep treating white hairs at higher energy.

The same Mayo page says laser hair removal should not be used on the eyelids, eyebrows, or surrounding areas, or on skin with tattoos, and that eyelid and eyebrow treatment is not recommended because of the risk of serious eye injury. The FDA archive lists laser side effects as blistering, discoloration, swelling, redness, and scarring, and says sunlight should be avoided while the skin heals. It also says the agency has received reports of serious and life-threatening side effects after large amounts of skin-numbing products used for laser hair removal, and that anyone considering a numbing product should follow a health professional's directions and use the lowest amount of anesthetic that professional recommends. Those warnings apply whether or not the hair is gray. They are not a technique guide.

Who regulates the practice

The archived FDA update draws a line that clinics sometimes blur. The Center for Devices and Radiological Health regulates electrolysis equipment and lasers. "The practice of professional hair removal is generally regulated by state and local authorities." The rules are not the same in every state, and this article does not map them. The Academy's own instruction is to have an experienced doctor perform laser hair removal, and a board-certified dermatologist or board-certified electrologist perform electrolysis. Asking who is licensed to operate the device where you live, who is in the room, and what happens if the skin blisters is part of the purchase, not a courtesy.

Sources

Primary regulatory documents, peer-reviewed studies, and the patient-guidance pages cited above:

1. American Academy of Dermatology. "6 ways to remove unwanted hair." aad.org.

2. American Academy of Dermatology. "Laser hair removal: FAQs." aad.org.

3. Mayo Clinic. "Laser hair removal." mayoclinic.org. Quotes checked against the live page on September 22, 2026.

4. Cleveland Clinic. "Electrolysis: Definition & Treatment." clevelandclinic.org.

5. U.S. Food and Drug Administration. 510(k) K241860, Diode Laser Hair Removal System, Beijing Winkonlaser Technology Limited. Cleared September 25, 2024. FDA PDF.

6. U.S. Food and Drug Administration. 510(k) database record K192620, SNA-001 Silver Photoparticle Topical Gel, applicant Sienna Biopharmaceuticals, Inc. Decision August 12, 2020. FDA database.

7. U.S. Food and Drug Administration / Sebacia, Inc. 510(k) summary K192620, SNA-001 Silver Photoparticle Topical Gel. FDA PDF.

8. U.S. Food and Drug Administration. Product classification OHT, light based over-the-counter hair removal, 21 CFR 878.4810. FDA classification.

9. U.S. Food and Drug Administration. "Removing Hair Safely." Consumer update, content current as of June 30, 2010, captured in a September 4, 2019 archive snapshot. The live fda.gov URL was not available for this article. Archive.

10. Sand M, Bechara FG, Sand D, Altmeyer P, Hoffmann K, Stuecker M. "A randomized, controlled, double-blind study evaluating melanin-encapsulated liposomes as a chromophore for laser hair removal of blond, white, and gray hair." Annals of Plastic Surgery. 2007;58(5):551–554. PubMed.

11. Goldberg DJ, Marmur ES, Hussain M. "Treatment of terminal and vellus non-pigmented hairs with an optical/bipolar radiofrequency energy source — with and without pre-treatment using topical aminolevulinic acid." Journal of Cosmetic and Laser Therapy. 2005;7(1):25–28. PubMed.

12. Bhat YJ, Bashir S, Nabi N, Hassan I. "Laser Treatment in Hirsutism: An Update." Dermatology Practical & Conceptual. 2020;10(2):e2020048. PMC.

13. Commo S, Gaillard O, Bernard BA. "Human hair greying is linked to a specific depletion of hair follicle melanocytes affecting both the bulb and the outer root sheath." British Journal of Dermatology. 2004;150(3):435–443. PubMed.

14. O'Sullivan JDB, Nicu C, Picard M, Chéret J, Bedogni B, Tobin DJ, Paus R. "The biology of human hair greying." Biological Reviews. 2021;96(1):107–128. PubMed.

15. Dermatology Times. "Help for light-hair laser reduction." February 2019 coverage of a Sienna Biopharmaceuticals announcement. dermatologytimes.com.