Red Light Therapy for Hair Loss: Is Your Pattern Listed?

Red LED light for hair loss sounds weird, but it’s a proven therapy that generates energy in hair follicles at the cellular level. So, what kind of red light grows hair?

Takeaways:

Studies on hair loss show that red and infrared lights are effective for re-growing hair. Specific wavelengths within the red and infrared range give photon (light) energy to follicles, waking them up from a dormant state.

The only problem is that only specific types of baldness respond to the treatment. When it does work, the success rate is over 93.5%. Speak with hair growth companies about your situation before buying. But then come back here to get the latest deals on hair growth devices.

Red Light Therapy for Hair Loss

Red light therapy grows hair for some baldness patterns but not all. Compare your hair loss pattern to the pictures in the male and female hair loss scales. If you are unsure if you are a good candidate, contact the red light therapy company for help.

Women use the Ludwig-Savin Classification, and men use the Norwood-Hamilton Classification. The patterns in the middle of each scale respond best to red light therapy. Red light therapy grows hair on women in four out of the nine female hair loss patterns and seven out of 12 male hair loss patterns.

Red light therapy is good for hair growth if you have the right hair pattern. When used correctly and on responsive hair patterns, red light therapy grows hair over 93% of the time. However, it does not work for some people, so checking your hair loss type before buying a device is essential.

The First Red Light Therapy Discovery Grew Hair

Red light therapy began when a researcher noticed that red laser light grew hair on mice. The field of red light therapy, now called Low-Level Light Therapy (LLLT) or photobiomodulation (PBM), began with red light to grow hair. Red light therapy hair growth companies advise checking your hair loss type against the male and female charts before committing to a device.

You Can Grow Hair At Home

The hair growth red lights you can buy for at-home use are as good as any treatment at the doctor’s office, except that your treatment times at home might be longer per session. When higher-powered lasers were the only hair growth delivery system, there was no at-home option.

Now that low-powered lasers and regular LEDs light the follicles, you have several choices for at-home hair growth treatment. There are so many choices, and I do not want to overwhelm you, so let’s start with the big hair growth companies. Then, I will show you a few exciting devices as well.

The best hair growth at-home device companies are HairMax, iRestore, and Kiierr. HairMax is the big guru, the first company to patent its devices, test them in published studies, and bring them to the consumer market. HairMax uses lasers in its cap, comb, and band hair growth lights, while Kiierr and iRestore use LEDs. While the effect over time is the same, the lasers have an advantage.

People often ask if LEDs are as good as lasers. Lasers allow you to have shorter treatment times per session. The hair will not grow faster or stronger because you use lasers, but the time you spend in treatment will be shorter. That is the advantage of lasers over LEDs. Don’t let anyone tell you LEDs do not work, though.

They do work; they grow hair as well as any laser. You might find a bargain buying an LED hair growth cap. Compare the treatment time per session in an LED cap to that of a laser cap.

How Red Light Therapy Regrows Hair

Mitochondria are organelles in cells, and cytochromes are proteins in them. Cytochromes absorb photons of light, kicking off the mitochondrial energy cycle. Dormant follicles grow hair when they absorb red light photons. Cytochrome (photoreceptor) proteins in the scalp’s cells absorb red light photons (energy particles) to stimulate dormant hair follicles. The light absorption kicks off an energy production cycle in the follicle cells.

Human cytochromes are particularly good at absorbing light in the red and infrared ranges. This is why red light therapy enhances many health processes, and low-level light therapy (LLLT) is so successful as a wellness modality. Besides stimulating dormant follicles, the new energy fortifies the growing hair, resulting in more and stronger hair.

Hair Growth Science

There is some evidence that infrared stimulates hair growth, but there is more evidence for red light success than infrared success.

What Science Says about Infrared for Hair Grow

Researchers combined 665 nm red with 808 nm infrared in a hair “scanner” device. Another group received red light therapy from a 665 nm red light cap without 808 nm infrared. The scanner group receiving red and infrared had better terminal hair density (more hairs) than the red hat group. Unfortunately, this is not an apples-to-apples comparison.

We do not know if the infrared or the different device type (hat vs scanner) caused the difference in the results. Did the infrared improve the results? On the other hand, was it using a scanner rather than a cap that created more hair density?

In a pulsed application, infrared is a hair removal wavelength as seen in this study at pubmed.gov: Comparison of the effects of 665 nm low-level diode Laser Hat versus and a combination of 665 nm and 808 nm low-level diode Laser Scanner of hair growth in androgenic alopecia.

What Science Says about Blue Light for Hair Growth

There is precisely one study testing blue light on hair loss, and it had positive results. In a 2021 Lasers in Medical Science study, twenty patients with androgenetic alopecia (normal hair loss) received two weekly treatments for 10 weeks of 417 nm blue light. 90% of the patients had an increase in hair shaft width at 10 weeks. 80% had improvement visible in before and after photos. See the study here:

Blue light-emitting diodes in hair regrowth: the first prospective study (opens in a new browser) If you use blue light at home, wear eye protection. Blue light is harmful to the eyes.

LEDs and Lasers Do Grow Hair

Both LEDs and lasers emit the right energy and wavelengths to grow hair. Lasers output light in columns that concentrate on small areas. The energy is strong because it is concentrated. LEDs output light more randomly, so they are “colder” than LEDs. Researchers using low-energy lasers and normal LEDs get the same results.

Healing takes place in low-energy light as well as high-energy light. LEDs with enough energy and the right wavelengths (colors) output photons that are as useful as laser photons. After hundreds of studies testing LED light on the body, there is no doubt that LEDs have the same effect as laser light. Healing comes from photons. So long as there are enough of them of the right wavelength, light stimulates healing energy creation and a nitric oxide response.

How Long It Takes

It takes red light therapy three to six months for you to see visible hair growth results. Hair grows at about 1/2 inch per month. As in the doctor’s office, only some types of hair loss respond to the therapy. For men, these hair loss types are Norwood Hamilton hair loss types IIa, III, IIIa, III-vertex, IV, IVa, and V; and for women, the hair loss types that respond to therapy are Ludwig Savin types I-4, II-1, II-2, and Frontal.

• HairMax says to expect visible hair growth in three or four months
• Kiierr advises that you will see hair growth in four to seven months using their products
• iRestore says that you will see results in three to six months using the iRestore helmet

All results depend on your skin and hair type, which responds to treatment, and you use the products as directed.

How Fast It Grows

Red light therapy does not make hair grow faster. The light energy stimulates dormant follicles so that they start growing hair again. The energy strengthens the existing and the new hair. When new hair appears, it grows at the standard rate: about 1/2 inch per month, naturally or through stimulation with red light.

Using infrared technology to test laser therapy on hair growth, researchers saw new hair appear as little as one week after the start of treatment. At-home hair therapy devices usually output red but not infrared light, but the effects of the two energies are often the same in other low-level light therapy. See the full study here: Use of the pulsed infrared diode laser (904 nm) in treating alopecia areata.

How To Grow Hair

To stimulate dormant follicles to grow hair, use a device that outputs one or more red wavelengths, as tested in hair growth studies. Hair growth devices designed to cover the scalp give you the best coverage. You can also use a bulb, panel, or handheld red light therapy source.

The key to any red light therapy success is correct dosing. Dosing consists of using the right wavelengths (colors) for the right amount of time to allow the body to absorb a healthy amount of photons. The right wavelengths range from 635 nm (nanometers) to 655 nm. These are shades of red that were tested in studies on growing hair. The body responds to ranges of wavelengths, so responding to more than one wavelength in the follicles makes sense. These are just the tested wavelengths. It is possible (and likely) that other wavelengths also stimulate dormant follicles.

The easiest way to use red light for hair growth is to obtain a hair growth cap, band, or comb and follow the directions to the letter. You have to get the dose right for it to work. Red light therapy for any goal is dose-dependent. Too little and too much light are equally useless. Several vendors sell models shaped for the human head. HairMax is the oldest and best-tested of these companies. iRestore and Kiierr are also significant brands.

Alopecia Areata

A few red or infrared studies successfully grew hair in humans and mice with alopecia areata. Still, none of these studies exactly matched the treatment you get in an at-home red light therapy device.

In the Super Lizera study, the hair grew using the “linear polarized” red and infrared light from a 2200 mW delivery system. That is much more powerful than a home device. The Journal of Cosmetic Laser Therapy 2006 study delivered 904 nm infrared light. While infrared is a viable red light therapy wavelength, the major hair therapy brands deliver red, not infrared light. Therefore, the study is not apples to apples with at-home treatment. The 2012 HairMax study grew hair on mice induced to have alopecia areata. This red light study is the closest to the real world. It grew hair in mice, not humans.

These are the studies below.

A 2003 study used the Super Lizera on fifteen patients with alopecia areata with patchy hair loss. 46.7% of the treated areas re-grew 1.6 months earlier than their untreated counterparts. Super Lizera literature claims their product reaches deeper than lasers or LEDs. Therefore, it is not comparable in that regard. However, Super Lizera treats with red and infrared, so this study confirms that red and infrared were associated with hair regrowth in patients with patchy alopecia areata. See the study here: (Linear polarized infrared irradiation using Super Lizer is an effective treatment for multiple-type alopecia areata.

A 2012 study confirmed the safety and efficacy of the HairMax LaserComb in mice with induced alopecia areata (an autoimmune disease). The 655 nm red-treated group of six mice had more anagen hair follicles at 6 weeks than the control group of six mice. See the study here: Effects of the Lexington LaserComb on hair regrowth in the C3H/HeJ mouse model of alopecia areata

Rogaine

You can use Rogaine (Minoxidil) with therapy, but wait an hour after application before starting that day’s laser treatment. The general rule is not to use hair products before treatment, but it is safe to use Rogaine as long as you wait an hour. You do not want the product in your hair to prevent light from reaching the follicles.

Treatment Schedules Used in Studies

Most device vendors instruct clients to do treatments every other day. If you are using a device from a hair growth company, follow their instructions to the letter. If you are making it up as you go using a “red light therapy” light without hair growth instructions, use the HairMax protocol.

Do treatments every other day, such as Monday, Wednesday, and Friday. Always leave a day between treatments. Always treat for the time instructed. The treatment time for HairMax devices ranges from 90 seconds to 30 minutes, and they range from very powerful (90-second treatment) to average power (30-minute treatment).

If we had the HairMax irradiance values for their devices and knew the target joules per treatment (the photons absorbed each session), we could calculate the treatment time for a generic device. However, to copy a protocol with a generic device, we need more data than we have, so we are going to have to wing it.

Since we do not know the HairMax or iRestore’s joules per treatment or irradiance per device, we can make an educated guess and hope for the best. Use the advised treatment time the manufacturer gives for a standard session three days a week. Ensure the light is the same distance from your head at each session.

Whether using a hair growth light or a generic red light therapy device, always use the same distance each session for the same time per session. Red light therapy works when the body receives the right amount of joules (photons per area) each session. Distance from the light and time per session dramatically affect the energy you receive. So keep the distance and time constant!

Hair Loss

As far as we know, red light therapy with red or infrared light does not cause hair loss. I have seen anecdotal instances of this question on the web, where there appear to be two situations going on. First, a natural shedding occurs in cycles, which might look like hair loss. If the hair is dead and shedding, the follicles are making way for new growth. That is normal and not hair loss.

However, there is also the case of people who use red light therapy and have visible, measurable hair loss. The question is, were they going to lose that hair anyway? Alternatively, did the light cause the loss?

The literature does not provide evidence that light causes hair loss, which means the question is unanswered. We know that most of the time, red and infrared of the right power and schedule will cause hair to grow. The final answer is that we do not know whether it can cause hair loss. It doesn’t appear so, but that’s as much an educated guess as anything.

Gray Hair

While I have seen anecdotal evidence that red light therapy reverses gray hair, there is no scientific evidence that it changes hair color. I have run several pubmed.gov searches but could not find evidence that light can change hair color. Hair color changes happen under some circumstances, but we do not have the science to prove that light changes hair color. Besides stimulating dormant follicles, the new energy fortifies the growing hair, resulting in more and stronger hair.

Conclusion

Red and infrared light regrows hair in some baldness types. The most scientifically tested devices come from HairMax.