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Red Light Therapy for Hair Growth: Everything You Need to Know
Dr Meena Zareie (GMC)
Medically reviewed by
Dr Meena Zareie (GMC)
Updated on May 9, 2024

Red light therapy for hair growth is a safe and effective form of low-light laser therapy (LLLT) which can help you achieve more luxurious locks.

As distressing as it can be to notice that your hairline is receding, your crown is thinning or your tresses only have half of their former volume, hair loss is also incredibly common. As many as 85% of men will be affected by it during their lifetime [1]. Although hair loss is more common in men than women, 55% of females will also have this experience [2].

The good news is that as science has evolved, researchers have also developed a wide array of solutions to restore your locks to their former glory. One of the least invasive – and completely painless – treatment options available is red light therapy for hair growth.

Red light therapy has been around for decades, proving its efficiency in treating wounds and repairing tissue, relieving pain and inflammation and resolving skin issues. Lately, it has also demonstrated promising results in stimulating hair regrowth, especially in people with androgenetic alopecia (male/female pattern baldness).

This article will tell you all you need to know about red light therapy for hair growth:

  • What red light therapy for hair growth is and how it functions
  • The effectiveness of this therapy and how it can be increased
  • The necessary number of red light therapy sessions and their cost
  • The safety and side effects of red light therapy
  • The right candidates for this treatment
  • What to look for when buying a home red light therapy device
Table of Contents

What is red light therapy for hair?

Red light therapy is a form of LLLT also known as photobiomodulation. It uses beams of a specific wavelength to stimulate your hair growth. Despite having “lasers” in its name, LLLT now mostly uses non-coherent light-emitting diodes (LEDs) [3], which can produce light of different wavelengths, with specific effects on the human body.

As its name suggests, red light therapy uses red or near-infrared beams of light, their wavelength ranging between 630 and 700 nm (660 nm is usually preferred). They penetrate the scalp and optimise cell functioning, which, in turn, stimulates hair growth.

wavelenghts of red light

If you are interested in this kind of therapy, you can get the best experience at a hair clinic, where you will benefit from state-of-the-art, medical-grade equipment. However, if you prefer getting red light therapy in the comfort of your own home, there are also smaller devices that you can buy and use anytime, such as LLLT brushes, combs or helmets [4].

person in LLLT helmet

What causes hair loss?

While there are many conditions and common scalp problems which can lead to hair loss, here are some of the most prevalent:

Androgenetic alopecia

Also known as male pattern baldness (or female pattern baldness), androgenetic alopecia affects 85% of men and 50% of women by the time they reach the age of 50.

In men, it causes hair loss in a specific pattern, especially around the hairline, temples and crown. In women, it is more diffuse and generally more visible on the crown.

This condition is caused by a complex set of factors, which include genetics, hormones and enzymes such as 5 alpha reductase. What happens is that the testosterone naturally produced by your body becomes transformed into a different androgenetic hormone called dihydrotestosterone (DHT). This hormone then binds to androgen receptors in the hair follicles, making them shrink and stop producing hair.

Early androgenetic alopecia, caught from the first signs of hair thinning and balding, can be treated with a variety of therapies or topical medication, such as Minoxidil or Finasteride. However, for the later stages, the most effective form of treatment is a hair transplant.

Norwood scale
Norwood Scale of androgenetic alopecia in men, stages 1-7
Ludwig Scale
Ludwig scale of androgenetic alopecia in women, types I-III

Alopecia areata

This type of hair loss is the result of an autoimmune condition, where the body’s white blood cells attack hair follicles, damaging them and preventing them from creating new strands. It affects approximately 2% of the population and manifests as irregular bald patches which appear suddenly on your scalp.

Unlike androgenetic alopecia, hair transplant for alopecia areata doesn’t usually work, because there is no safe donor area (your antibodies would be attacking the implanted hair follicles as well).

bald spot due to alopecia areata

Telogen effluvium

This is not a disease of the hair or scalp, it is actually a condition which occurs when someone is under great amounts of stress or has suffered significant trauma.

What it does is extend the telogen (resting) phase of the hair growth cycle, making fewer new strands grow out. The result is diffuse thinning of the hair, without any discernible pattern to it.

As soon as the stress is alleviated, this condition should also subside and your hair should start growing back.

examples of diffuse thinning

How does red light therapy for hair work?

In order to understand how red light therapy works, it is necessary to know a few things about the way your hair grows. The hair growth cycle repeats itself every 3-7 years and has 4 distinct phases:

hair growth cycle
  1. Anagen – the majority of your hair follicles (80-90%) are in this phase, where they receive a sufficient, nurturing blood supply, making strands grow out healthily.
  2. Catagen – also known as the transition phase, when the hairs become detached from the blood supply and the hair bulb starts to break down. Approximately 1-5% of your tresses are in this stage at a time.
  3. Telogen – this is the resting phase, when hairs stop growing, allowing the follicle to rest. 10-15% of hairs are normally in this stage.
  4. Exogen – during this phase, you will start shedding, losing 50-100 hair strands every day. This is normal and nothing to be worried about. At the end of this stage, the cycle resumes and strands start growing once more.
informational graphic showing where red light penetrates on the scalp

While the scientific community has not yet reached a definitive agreement regarding the exact mechanism which makes red light therapy work, researchers do have some solid theories.

The most widely accepted is that as focused red or near-infrared light penetrates your scalp, it stimulates an enzyme called cytochrome c oxidase found in the mitochondria of our cells [5]. This creates a biochemical reaction, increasing mitochondrial activity, which leads to releasing nitric oxide and producing higher quantities of a substance called adenosine triphosphate (ATP) [5].

ATP has a role in transporting energy to your tissues, providing the hair follicles with the necessary resources to remain in the anagen phase for longer and thus stimulating strand growth and postponing their natural shedding.

Does red light therapy block DHT?

There are currently no scientific studies linking red light therapy to DHT blocking. While some treatments for hair loss, such as Finasteride, do work by blocking this androgen hormone, other therapies, such as LLLT, rely on other mechanisms of action to stimulate hair growth.

If you are interested in preventing hair loss, you might achieve significantly better results if you combine red light therapy with a course of topical hair growth medication.

Taking a look at the Minoxidil before and after treatment photos or learning more about Finasteride results can restore hope in regaining a full head of hair. You can even try Minoxidil combined with Finasteride for a stronger approach. Just be sure to get the recommendation of a hair specialist before starting treatment, to be certain you are a good candidate (e.g. Finasteride is not recommended to pre-menopausal women).

There are also natural DHT blockers that you can use if you don’t want to take medication for your hair, such as caffeine, rosemary oil or pumpkin seed oil.

Is red light therapy good for your hair?

Yes, red light therapy has been scientifically proven to promote hair growth, improving both strand density and thickness. Numerous studies have emphasised its benefits. Here are a few telling examples:

  • A study performed on 47 women affected by early-stage female pattern baldness revealed that, after 60 sessions of home treatments with a red light therapy helmet, the research group (the women who received the real treatment) showed a 37% hair growth increase in comparison to the placebo group [6].
hair count before and after red light therapy
Hair count before and after red light therapy [6]
  • Another, almost identical research on 44 women experiencing androgenetic alopecia produced an even higher hair growth increase than the placebo group: 51% [7].
  • A similar study was conducted on 44 men in different stages of male pattern baldness. They also received 60 sessions of home treatments with the same type of red light therapy helmet and the research group experienced 35% increased hair growth compared to the placebo group [8].
  • A randomised, double-blind clinical trial performed on forty subjects of both genders with androgenetic alopecia monitored hair growth increase after 8, 16 and 24 weeks of red light therapy. Results showed significant improvement in hair density and thickness after the 24th week of treatment [4].
results of red light therapy
Before and after 24 weeks of red light therapy [4]

Evidence thus shows that red light therapy is indeed good for your hair, as it stimulates strand growth. Even though most of these studies were performed on people with androgenetic alopecia, good results have also been reported for alopecia areata, telogen effluvium, etc [9][10].

How to improve the effects of red light therapy

Research shows that red light therapy is more effective when it is combined with hair growth medication, such as Minoxidil or Finasteride.

A meta-analysis of 15 studies, comprising a total of 1172 patients with androgenetic alopecia revealed that the combination of red light therapy with Minoxidil or Finasteride yields better results in increasing hair count than either of the two treatments on its own [11].

However, it is recommended to see a dermatologist or trichologist before taking any hair growth medication. That is because they can have side effects which may be harmful for some people (e.g. Finasteride is not recommended to pre-menopausal women, as it can cause hormonal imbalances or foetal malformations).

Other things that you can do to boost the effect of red light therapy might be:

Is red light therapy for hair loss safe?

If you are worried about the potential side effects of using red light therapy on your hair, you can rest entirely at ease. There is a general consensus among researchers that this procedure is safe and can be used frequently with no serious negative consequences to your tresses, scalp or overall health.

From all the studies that have been performed so far, only a few have reported minor side effects: pruritus (itching), acne and tenderness. These symptoms resolved on their own within 2 weeks [12]. However, most research has revealed no adverse effects [6] [7] [8], so rest assured that it is very unlikely for red light therapy to cause any kind of harm to your hair and scalp.

However, since this therapy is light-based, people who are prone to light-induced seizures (e.g. epilepsy, migraines, etc.) should consult their healthcare provider before using it.

How often should you use red light therapy for hair growth?

Since there are no safety concerns associated with red light therapy, it can be used as often as you’d like. There is no risk of overdosing and you should be fine if you choose to treat yourself to some daily radiance.

However, dermatologists [13] recommend getting 20-30 minute treatments 2-3 times a week for optimum results, if you are using medical-grade equipment. If you are using home devices, it is best to undergo 10-20 minutes of red light therapy 3-5 times a week.

How long does it take for red light therapy to grow hair?

The amount of time needed to start seeing results from your red-light hair treatments depends very much on the cause of your hair loss and on your overall hair and scalp condition. Less advanced hair loss, with limited damage to the follicles, should respond better to the red light, allowing you to see improvement in hair density and thickness sooner than late-stage alopecia.

On average, it is not unusual for a full course of treatment to last 3-6 months (or over 20-30 sessions). So keep in mind that this is a marathon, not a sprint and don’t be discouraged if you don’t see new hair growth after the first few sessions.

Is red light therapy for hair painful?

No, fortunately, red light therapy is not painful at all. While it does involve applying focused light to your scalp, the devices used only emit low amounts of heat. This can make you feel pleasantly warm, but can in no way burn or damage your skin. If you feel that your eyes are bothered by the shine, you can feel free to close them and relax during the session. Normally, all you should be experiencing is a soothing, comfortable sensation.

If you feel a burning sensation while getting red light therapy, it is a good idea to see a dermatologist or trichologist, because there are a variety of conditions which can produce burning scalp and hair loss.

How much does red light therapy cost?

The cost of red light therapy depends on the number of sessions you need to undergo, the type of device used and the clinic where you are getting your treatment.

On average, in the UK, the cost of a single treatment session is in the vicinity of £45. Since, depending on the extent of your hair loss, you might need at least 20-30 sessions to achieve satisfactory strand growth, a complete course of therapy might cost around £1,125 in total [14].

While some clinics may offer lower prices, it is important to learn about the type of red light therapy device they use before making a decision. Older machines may be slower or less effective than newer, better-optimised models.

Purchasing your own home device for red light therapy and self-administering the treatment is also an option. Depending on the type and quality of the device you choose to buy, it can cost less than a hundred to more than a few thousand pounds.

However, please be advised that not every home product on the market is safe and effective. A price which sounds too good to be true might hide poor quality or even counterfeit wares.

It is generally a good idea to only purchase therapeutic devices from reputable brands, research the necessary product specifications and check out consumer reviews before buying.

Choosing a home red light therapy device

When opting for a red light therapeutic home device, it is important to select high-quality products and avoid any possible scams. Here are some of the main things to look for when buying a red light therapy device:

Wavelength range

Red light normally ranges between wavelengths of 630-750 nanometers. However, some devices have several modes, which also offer near-infrared (810-850 nm) or infrared (over 900 nm) light options.

If you would like to use this device for additional purposes than just hair regrowth (e.g. reducing tissue inflammation, pain management, skin care, or even alleviating symptoms of depression), you may want to opt for a device with a wider wavelength range.

Light intensity and radiance

This measurement lets you know how bright and powerful the light emitted by the device will be. The higher the intensity of the product, the faster and more efficient the therapy will be.

Choosing a low-powered device might yield insufficient amounts of red light for optimum benefit.

Number of LEDs

Red light is often emitted by therapeutic devices through an arrangement of larger light-emitting diodes (LEDs). The more LEDs the product has, the more light it emits and the faster and more efficient it is.

Treatment area

If you plan to use this therapy for hair growth alone, products designed for a targeted, smaller treatment area will likely suffice (such as a helmet or a hand-held device).

However, if you also plan to use it for more extensive body issues or if your family members might also use it for different purposes, you might want to look at larger, full-body options.

User-friendly features

Helpful features, such as programmable timers or adjustable settings can make a difference when selecting a red light hair therapy device. So can a clear, visible interface which is easy to read and interact with.

Customer reviews

Just like in the case of any other product, insight offered by people who have already bought and used the red light therapy device you are interested in can be extremely valuable. Reviews can speak to product efficiency and usability and can also warn you about hidden flaws in its design or functioning.

Who is a candidate for red light therapy?

If you are experiencing diffuse or patterned hair thinning, especially in the early stages, you may be a good candidate for red light hair therapy.

Extensive research[4][9][10] has shown that it is as effective in men as it is in women, especially when it comes to hair loss due to the following conditions:

However, ask your healthcare provider if this type of therapy is suitable for you if your hair loss is due to scarring alopecia, as you may not be able to obtain good results (hair follicles may be destroyed in the balding area).

Common myths about red light hair therapy

In time, a number of misconceptions have emerged in relation to red light therapy for hair. Here are a few of the most common and the reasons why they are not true:


1. Red light therapy can burn your scalp

The devices used for LLLT never emit enough heat to cause any damage to your skin. The most you may feel is some soothing warmth, which should not cause discomfort.

If you are experiencing a burning sensation while using a home red light therapy device, turn it off immediately, as it might be counterfeit and potentially harmful to you.


2. Red light therapy is pseudoscience

While there are many snake-oil treatments out in the world, the effects of red light therapy on your hair are scientifically proven. Numerous studies conducted on thousands of people in total have found that after 3-6 months of sessions, this type of LLLT does indeed stimulate an increase in hair thickness and density [6][7][8].


3. Red light therapy changes your hair colour

Red light therapy does not contain any particles which can interact with the pigment in your hair. It will not influence the aspect of your hair and it will not interact with any styling product, such as dye.


4. Red light therapy can cause skin cancer

This concern is understandable, considering that exposure to regular sunlight can increase your risk of skin cancer if not using protection. However, unlike sunlight or tanning beds, red light therapy devices do not emit UV radiation. They are thus safe to use on your skin and scalp without fear of developing melanoma.

Hair loss treatment alternatives to red light therapy

If you are interested in other solutions to prevent your hair loss, here are some of the most popular and effective:

Hair transplant

This is a simple and effective procedure where hair from a healthy donor area (usually the back of the head) is extracted and reimplanted in the balding spots.

The best hair transplant clinics offer experienced surgeons and state-of-the-art techniques, such as follicular unit transplantation (FUT) or follicular unit extraction (FUE) to make sure you get a perfectly natural post-transplant look.

Unlike some other treatments, hair transplant is permanent, solving your hair woes for good. See our most convenient clinic location for a hair transplant consultation.

Topical hair growth medication

Medication such as Minoxidil and Finasteride can help limit shedding and stimulate hair growth and steroid creams could alleviate the scalp symptoms of alopecia areata.

However, they should be used at the recommendation of a medical specialist, as they could have adverse effects or not be effective for your condition.

Derma rolling for hair growth

Rolling a small, handheld device, covered in hundreds of very fine needles, on your scalp can improve blood flow and stimulate hair growth.

Platelet-Rich Plasma (PRP) therapy

A PRP hair treatment involves drawing a small quantity of your blood and injecting it into your scalp. This provides nourishment to hair follicles, improving hair density and thickness. Learn more about the success rates of PRP hair treatments.

Naturally, the efficiency of any treatment option greatly depends on the cause of your hair loss. If you are experiencing unexplained hair shedding, it is very important to be diagnosed by a specialist.

Book a consultation today with one of the renowned trichologists at Wimpole Clinic. They will conduct blood tests for hair loss and based on the results, they will recommend the best hair loss treatments for women, or, by case, the most efficient hair loss treatment for men.

Red Light Therapy for Hair Growth: Everything You Need to Know, Wimpole Clinic

Dr Meena Zareie (GMC)
Medically reviewed by Dr Meena Zareie (GMC)Updated on May 9, 2024
The Wimpole Clinic offers FUE Hair, Beard & Eyebrow Transplants & Trichology.
Talk to a specialist ☎ 020 7935 1861.

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