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Medical Efficacy of Laser Hair Treatment

  1. Jan 5, 2010 #1


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    I apologize if threads on this topic have been posted already. I don't frequent the medical sciences forum. My question is whether there are any rigorous scientific results published in peer-reviewed journals on the efficacy of what seems have been dubbed "low level laser therapy" (LLLT) as a treatment for male pattern baldness (i.e. laser light that stimulates follicles/cells to regrow hair).

    It seems to be a bit of a cottage industry, with a bunch of clinics springing up and business models developing. I went to a clinic for a free consultation. Of course, I was an "excellent" candidate. What they are offering is very expensive, and the overwhelming negative reviews of people on this forum who have actually tried out or are in the midst of trying out the very same clinic:


    have me convinced that it is a scam, at least in the sense that the same products (e.g. portable "laser combs") are being offered through the clinic at significantly higher prices than similar products that manufacturers will just sell you (by a factor 2-3!)

    Yet, if you go to the company that makes the "HairMax" laser comb, claimed to the only one in the industry to be FDA approved for marketing as a hair loss treatment product, and you look a little more deeply in to said "FDA" approval, you just find that all the FDA said was that the device was similar enough to other "predicate" devices sold since before some date in the 1970's for similar *enough* applications that the company in question could skip a bunch of red tape and get approval to market it now. In short: approved for marketing, ruled as non-harmful. But no ruling one way or another on its effectiveness.


    The website is quite misleading in that regard. In fact, only one of their models is approved in this manner, so that if you click on the link for the other model, it says "NOT FDA APPROVED!" Not for sale in the USA! In fact, the website of their Canadian subsidiary has a much wider range of models, probably for this very reason! Quite hilarious.


    As for the efficacy, the only thing I came across was this YouTube video from a Dr. Alan Felder calling it "junk science", and demonstrating that a laser beam (presumably of the same wavelength range and power output as those being sold for LLLT, although he makes no effort to quantify anything) cannot even penetrate a piece of tissue paper, therefore there is no way it could reach the hair follicle to stimulate it. I take issue with some of his statements, which demonstrate that he does not have a very good knowledge of physics. For instance, he says that the "dot becomes bigger", losing its "laser character" and turning into "ordinary red light," becoming effectively the same as red LED light shone into the skin. Well, as many on this forum will know, his first point just means that the light gets scattered. Whether or not it "loses it's laser" character is question that must be posed more specifically. Obviously the collimation of the beam is lost, but the monochromaticity and the coherence are preserved. He makes no reference to these concepts, and erroneously states that the light is exactly the same as red LED light which probably has a much wider bandwidth.

    That having been said, my nitpicks of his physics are probably irrelevant, particularly in the absence of any evidence that the aspects of "laser character" that are retained actually do anything. Who is to say whether that wavelength is more effective in stimulating cells than other ones? And he may have a point about scattering (although he did not use the term). When we say a laser diode is much more "powerful" than an LED, I'm sure we're talking about intensity (W/cm2). If the laser light is diffused and scattered before significant power can reach the depth required, then what good is that? Again, I just don't *know.* He makes no effort to present anything quantitative, and he does hair transplants, which means he has as much of a vested interest in all of this as anybody else.

    The only info I could find about the depth of hair follicles is that they are located in the dermis, below the epidermis, and that these two layers vary in thickness from 0.05 mm - 1.5 mm (epi) and 0.3 mm - 3 mm (dermis) depending on where on the body you look.
    Last edited: Jan 5, 2010
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  3. Jan 6, 2010 #2
    Hi, this is exactly the kind of question I would like to get set straight, when I googled and found this forum. I'm a physician and skeptical. To my knowledge, we have no other light sensitive molecules in our body than in the rods and cones of the retina, and in the melanocytes of the skin. The melanocytes do not produce hair, they protect us from UV harms. The LLLT proponents claim that there is an effect on cytochrome-c (an enzyme). I shall look into that when I get enough time.

    Not being a physicist, I'm having a problem with all these medical laser (LLLT) claims, and I'd pose the question in the same (ignorant?) way as above: Is the beam still "laser" after having penetrated and been scattered by the first surface it encounters -- and not burns itself through? Is coherence and monochromaticity the key, not collimation?
    Specifically at the moment, I'm trying to debunk claims that LLLT can cure tinnitus and hyperacusis. /Best regards. O.
  4. Jan 6, 2010 #3


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    Welcome to the forum okjhum, we will be looking forward to hearing more from you.
  5. Jan 6, 2010 #4


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    Hi okjhum,

    Well, basically I went back to the clinic I mentioned in my first post, which is called Biothera. I played it cool and led them to believe that I was still as taken in with their song and dance as I had been the first time during my consultation (when, in reality, serious doubts had grown in my mind since then). The kicker was when the "program coordinator" mentioned to me that this laser penetrates to a depth of "650 nm, right down where it needs to go." Yet, earlier in her presentation, she had claimed that the laser light would reach the follicle, where it would "break up the DHT" (some form of testosterone?) that was preventing the blood supply from reaching it. It seems obvious that light penetrating only to a depth of hundreds of nm doesn't get anywhere near the follicle. Wikipedia says that living cells are about 10 μm = 10,000 nm in size. The follicle is presumably made up of...a LOT of living cells right? Not to mention it is located in the dermis, and I think (can anyone confirm?) that is ~ 1 mm down. So this light is penetrating to a depth that is 100 times smaller than the average cell, and it barely gets one ten thousandth of the way down to the follicle! (1 mm = 103 μm = 106 nm vs. the light going down ~ 102 nm.)

    So there are two possibilities:

    1. The lady was correct and the light only penetrates of the order of a wavelength, calling into question how it can actually do anything.

    2. The lady was mistaken/confused. After all, she was quoting me numbers like "650 nm", and made other statements like, "dermatologists are using laser light to treat wrinkles, but that one only goes down to 550 nm." Since these sound like wavelengths of light, maybe she was confusing the wavelength of the laser with its depth of penetration into the skin?

    Either way, the inconsistencies and the fact that she didn't seem to know what she was talking about led me to believe that Biothera is full of BS, and I'm not going to waste any of my money on them. I'm going to talk to my doctor about my hair loss tomorrow, and since Rogaine has not been effectual thus far for me, I'm going to ask him if I would be a good candidate for Propecia at a low dosage. I'm still young and my hair loss is not really evident to the casual observer. It's just a slight receding of the hairline around the crown and a slight thinning in the front.

    The efficacy of laser hair treatment remains an open question, since none of the info the lady at Biothera has provided seems reliable. My dad, who is a pharmacist, told me that he was under the impression that the medical community was unsure of what to make of it either, but that they felt that the claimed scientific basis behind it was sketchy, and no rigorous studies had been conducted. Okjhum's post strengthens my supposition that that is the case.
  6. Jan 9, 2010 #5
    Hi all,

    I think the lady was confusing several aspects claimed by [PLAIN]http://en.wikipedia.org/wiki/Low_level_laser_therapy" [Broken] [Broken].

    Firstly, 650-nm refer to the wavelength of light the laser diodes commonly used in LLLT for alopecia areata treatment. 650-nm is basically a red color diffusion and some LLLT studies since a decade seems to prove that this wavelength is the most adapted to hair treatments.
    Since the higher the wavelength, the greater the penetration, 650 nanometers should reach the depth of the follicles for biostimulation. This is what the LLLT industry in hair treatment claims.

    Secondly, LLLT advocates in hair treatment do not claim that LLLT blocks DHT. They claim LLLT has another mechanism on hair follicle based on what LLLT studies called laser biostimulation. The mechanism should be photochemical rather than heat-related and depend mostly on wavelength used, energy densities of the irradiation (in Joule per cm(2)) and pulses (peak power and repetition rates).

    Most of LLLT hair treatments use 650nm / 5mW diodes for achieving somewhere around 3-6 joules of energy on each square centimeter of scalp (20 minutes per treatment, twice a week).

    Products will vary mainly on the number of diodes. As you can imagine, the more they have the more you can treat.

    From my point of view, as [PLAIN]http://en.wikipedia.org/wiki/Low_level_laser_therapy" [Broken] [Broken] says "the treatment is not yet accepted as routine medical therapy".

    Excuse me for my bad grammar. English is not my first language,
    Last edited by a moderator: May 4, 2017
  7. Jan 16, 2010 #6
    So, I suppose that this and other wavelengths are included in ordinary sunlight. What would the biological difference be for 'cepheid' if he walked bareheaded in the sunlight and got a complete, multi-frequency make-over for free instead of paying a lot for some very restricted light???
  8. Jul 9, 2010 #7
    The use of laser for hair growth is somewhat controversial. This is because there are medical practitioners who do not believe that low level laser therapy or LLLT works against hair loss and there are other physicians who regularly use it in their treatment methods.
    I would also advise to read myhairway book, written by M.Gardson ..it contains a good method for hair growth
  9. Jul 13, 2010 #8
    The mechanism by which DHT forms is not going to stop even if it is destroyed by a laser. Pretend for a moment that the laser does as advertised; you would have to have these treatments constantly, and I'm not sure that even that would yield the desired results. It may be that it works, I have not studied this, but based on the facts presented it sounds laughable. What is not laughable is the desperation which drives people to pay for these treatments. To be fair, this woman could be full of ****, and LLT could still work, or she could be giving you hard figures that mean nothing. The issue, is that this has not BEEN rigorously tested in an impartial and scientific manner.
  10. Jul 14, 2010 #9
    I'm repeating myself, but IF there is any beneficial photostimulation effect at all, why not go bareheaded in the sunlight and get a complete, multi-frequency, multi-depth make-over for free instead of paying a lot for some very restricted light that looks more like bogus than anything else!
  11. Jul 14, 2010 #10
  12. Aug 26, 2010 #11
    sorry, I'm not a physician or a physicist. I'm a regular consumer looking for solutions to my husband's baldness. :) Reading from the items posted on this forum, does it mean that laser hair treatment doesn't work at all? I've seen the ads on newspapers and wanted to suggest this to my husband (who's now depressed because of his hair loss) but I wanted to be sure we're not wasting money. I also heard about a product named Propecia, but couldn't find reviews about it.

    Has anyone tried laser hair treatment? What are its side effects? Will it cause cancer? Is it harmful? Thanks for your response!
  13. Aug 28, 2010 #12
    This is my opinion, but no, I don't believe it's even marginally effective; it is a scam.
  14. Dec 10, 2010 #13
    A nice topic and informative sharing. keep good work
  15. Dec 10, 2010 #14
    You commented on a thread from August to say that? I'm confused.
  16. Dec 10, 2010 #15


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    They responded after a (now deleted) spam post revived the thread.
  17. Dec 10, 2010 #16
    Oooooh, I see.
  18. Jan 31, 2012 #17
    There still is no evidence for laser therapy for hair regrowth, as far as I know.
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