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Learn MoreRead Time: 10 minutes
When I was diagnosed with male pattern hair loss, I immediately picked up some Rogaine and signed up for something called low-level laser therapy.
It was 2007, and at the time, many doctors were parading low-level laser therapy as a hair loss savior – a treatment that would not only stimulate hair regrowth, but also prevent future hair loss even after stopping the therapy. The cost for eight sessions? $2,000. Expensive, but given the hype, I had to try it.
After eight laser therapy sessions, what were my results?
I’ll save you the suspense: Rogaine + low-level laser therapy did not regrow my hair.
With that said, I can’t dismiss low-level laser therapy as an effective hair loss treatment. In fact, under the right circumstances, low-level laser therapy may be a very effective hair regrowth tool. This article uncovers why.
After reading, you will know:
Low-level laser therapy (LLLT) is “therapeutic” exposure to red or near-infrared radiation.
For hair loss sufferers, this involves placing the scalp under infrared-emitting laser diodes. A typical laser therapy session lasts from 20-60 minutes. You can complete them at a doctor’s office, with a take-home laser helmet, or even with a laser brush.
While the treatment looks ridiculous, it helps to think about laser therapy in this context:
Laser diodes for hair loss emit red light at wavelengths of 630-670 nanometers. The sun emits wavelengths from from 250 to 2,500 nanometers.
Low-level laser therapy is simply exposure to one part of the sun’s spectrum for a controlled period of time. And it turns out that some wavelengths show serious benefits to human physiology – from wound healing to inflammation resolution to even hair recovery.
Scientists discovered laser technology in 1960. Soon after, researchers began testing its effects on health. What they found? While some wavelengths can blind you, other wavelengths can…
Then researchers discovered laser therapy’s effects on hair health. The results were promising and paradoxical…
On the one hand, laser therapy can permanently remove body hair. On the other, it can accelerate hair growth rates in mice and even increase hair follicle proliferation in humans. The question was… Why?
How can laser treatments both encourage faster hair growth or permanently remove hair? How can it accelerate wound healing or permanently blind us?
It all depends on a laser’s wavelength, pulse rate, session duration, and frequency of exposure.
For example: a laser operating at wavelengths of 630-670 nanometers can encourage hair follicle proliferation (hair regrowth). But at wavelengths of 690-1100 nanometers, a laser can overheat a hair shaft, damage soft tissues around a follicle, and destroy the hair. There’s a very fine balance between two opposing effects.
And while we know that low-level laser therapy (LLLT) helps stop or reverse hair loss or hair thinning, no one yet knows the optimal…
This is even well-acknowledged in the literature:
“Although LLLT is now used to treat a wide variety of ailments… a large number of parameters such as the wavelength, fluence, power density, pulse structure, and timing of the applied light must be chosen for each treatment. A less than optimal choice of parameters can result in reduced effectiveness of the treatment, or even a negative therapeutic outcome. As a result, many of the published results on LLLT include negative results simply because of an inappropriate choice of light source and dosage.”
This is why I don’t consider my results from low-level laser therapy (LLLT) to represent the treatment’s potential.
No, I didn’t regrow any hair while trying LLLT. No, my rate of hair thinning didn’t slow or stop. But remember: I tried LLLT in 2007 – ten years ago. Yes, I did it at a doctor’s office and under physician supervision. But maybe eight sessions wasn’t long enough. Maybe the specified wavelength wasn’t right. Maybe the diode diameter wasn’t wide enough. I’ll never know. But a lot can change in ten years – including LLLT’s best-practices for hair recovery…
Except here’s one thing that hasn’t:
We still don’t know exactly how low-level laser therapy regrows hair.
No one knows. But there are plenty of theories.
In fact, there are so many proposed mechanisms of how low-level laser therapy regrows hair that entire papers have been published just to summarize them. Here are five worth mentioning:
1. The laser’s heat activates heat shock proteins
Some of these heat shock proteins – specifically HSP27 – are utilized for cell proliferation and division. And in the scalp, increasing these proteins also increases follicular stem proliferation. In other words, it encourages hair regrowth.
2. The laser’s light increases tissue oxygenation
When the infrared light hits a tissue cell, that light separates nitric oxide from an enzyme called cytochrome c oxidase (CCO). When nitric oxide binds to the enzyme CCO, it displaces oxygen in the cell and decreases cellular respiration. LLLT dissociates nitric oxide from CCO and, in doing so, increases cellular respiration and tissue oxygenation.
Lower tissue oxygen levels are observed in balding regions of the scalp. Anything that improves scalp tissue oxygen levels should also encourage hair regrowth. (Note: for more information, read this).
3. The laser’s light increases blood flow
Where there’s low oxygen, there’s low blood flow. This is because blood carries oxygen to the cells – so it’s no surprise balding regions have lower amounts of both.
This is where infrared light comes up. Just as infrared light dissociates nitric oxide from skin tissue cells, it also separates nitric oxide in the cells that make up our blood vessels. Nitric oxide behaves differently depending on where it is in the body. In the blood, nitric oxide actually encourages vasodilation (widening of vessels), and so here, more nitric oxide increases blood flow. In the capillary networks, LLLT’s separation of nitric oxide is a good thing, but for completely different reasons.
4. The laser’s light generates acute tissue inflammation
Because LLLT increases cellular respiration and tissue oxygenation, it also increases the activity of reactive oxygen species (ROS) in the scalp tissue. You might’ve heard of these reactive oxygen species (ROS) from anti-aging fanatics. Too many ROS can increase oxidative stress and thereby accelerate aging.
But in acute doses, ROS are actually necessary for cell proliferation, inflammatory responses, and even immune function. LLLT increases ROS to a therapeutic (read: not detrimental) level in scalp tissues. The ROS activate protective genes which encourage cell proliferation, along with specific growth factors associated with hair regrowth.
5. The laser’s light can inhibit 5-alpha reductase
5-alpha reductase is the enzyme that converts free testosterone into tissue DHT (dihydrotestosterone). The more 5-alpha reductase, the more DHT collects in our scalps.
On the plus-side, the evidence for DHT’s role in hair loss is strong: 1) DHT is elevated in balding scalp tissues, 2) men who are castrated before puberty (and can’t produce much DHT) never go bald, and 3) men who lack the 5-alpha reductase enzyme don’t lose their hair later in life. This is why drugs like Finasteride and Dutasteride were made. They’re 5-alpha reductase inhibitors. They reduce the amount of DHT that collects in balding scalp tissues.
With that said, DHT’s role in pattern hair loss is still debated! We aren’t yet sure if elevated scalp tissue DHT is the cause of male pattern hair loss… Or rather a symptom of chronic inflammation.
But reducing scalp tissue DHT may help slow hair loss, stop it, or even recover a bit of hair. So if LLLT inhibits 5-alpha reductase might just be one (of many ways low-level laser therapy that means that anything that inhibits 5-alpha reductase in the scalp might also help halt hair loss.
This all sounds good. LLLT might be a viable hair recovery treatment. But before you go out and drop thousands of dollars on laser therapy, here’s what you need to know.
Problem #1: LLLT Products Vary In Hair Regrowth Efficacy
There are three different kinds of laser therapy treatments:
While these all use the same technology, I have significant reservations about laser combs.
The biggest problem is that there’s no easy way to track how long each part of your scalp has been exposed to the laser diode. Why? Because you’re combing your hair and moving the diodes the entire time. There’s no way to know if each part of your scalp is getting enough exposure for a theraputic effect.
The laser combs are also uncomfortable to use. And I’m speaking from personal experience. I bought a $300 laser comb back in 2009 and never liked using it. I feared damaging my eyes each time a laser diode flashed into my retina. After a few months (and no results), I put the comb in my closet and forgot about it.
So if you’re going to try laser therapy, I recommend that you should opt for a helmet over a comb. Doing so might cost more, but it’ll help you track scalp coverage and avoid eye injuries.
Problem #2: There Are No Laser Therapy-Hair Regrowth “Best Practices”
Of all the doctors that offer in-house laser treatments, none of them seem to agree on which settings are best for hair recovery.
I’m talking about session duration, session frequency, laser diode size, and wavelength (among others). Many doctors have different setups, and very few doctors share which settings work for their patients, and which settings don’t.
This makes it hard to find the “best” in-house LLLT provider.
You can’t just walk into any doctor’s office offering LLLT and expect hair regrowth. There’s just too much variation in settings and a lack of information-sharing across in-office laser therapy providers.
So, you need to do your homework. Here are two ways to find a hair loss laser treatment that actually works:
1. Find a study on LLLT that achieved significant hair regrowth on humans (not mice)…
…Then buy the exact same laser. Replicate that study’s methodology on yourself – the session duration, session frequency, wavelength, and everything in between. Don’t be afraid to email authors of hair loss-laser therapy studies. They take forever to get back to you, but they do reply.
There are also a few laser therapy providers who do this work for you – building custom laser helmets based on study findings.
2. Find someone who achieved significant hair regrowth while trying low-level laser therapy
These people exist in real life and on hair loss forums. Track them down, and then make sure they’re not connected to any LLLT affiliate programs. If they have before-after photos, that’s even better. Then find out their exact routine – session duration, session frequency, helmet used, doctor visited, etc. Match their exact methodology and routine.
If you deviate from either option, you could find yourself in scammy territory. Low-level laser therapy products are thousands of dollars. You don’t want to make a purchase mistake with that much money on-the-line.
The evidence is clear: low-level laser therapy (LLLT) shows promise in slowing, stopping, or even reversing hair loss. With that said, researchers still haven’t uncovered…
Low-level laser therapy is also expensive, and if you’re going to spend thousands of dollars, do your homework so you avoid scammy laser products. Either 1) replicate the methodology of human hair regrowth-LLLT studies, or 2) track down someone who’s seen success with LLLT, and then replicate their methodology.
In order to advance low-level laser therapy and its effectiveness for hair recovery, LLLT providers should start sharing their “best practices” with physicians. Doing so will get us closer to uncovering the mechanisms and optimum settings for hair recovery.
One last note: I have no recommendations for (nor am I affiliated with) any LLLT products.
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