Red Light Therapy: Are we all just sitting under expensive red bulbs?

Red light therapy has become difficult to ignore.

From professional LED systems in aesthetic clinics to increasingly sophisticated home-use masks, panels and handheld devices, we’re being told that a few minutes under red light can improve everything from fine lines and skin texture to inflammation, recovery and hair growth.

Some of the claims are substantial. So is there good science behind red light therapy, or have we simply found a particularly photogenic new wellness trend?

The answer is more interesting than either extreme.

First, what is red light therapy, actually?

The scientific term you’ll frequently encounter is photobiomodulation (PBM).

Rather than using light to heat or deliberately damage tissue, as occurs with some laser and energy-based treatments, photobiomodulation uses non-ionising light at particular wavelengths to produce biological responses within cells.

Red light typically falls in the 600–700 nm region of the spectrum, while near-infrared light uses longer wavelengths, typically 700–1,100 nm. Different wavelengths penetrate tissue to different depths, which is one reason why simply describing a device as providing “red light therapy” doesn’t tell us very much.

What’s supposed to be happening inside the cell?

This is where things become more interesting.

One of the principal proposed mechanisms involves the mitochondria, the structures responsible for producing much of the energy used by our cells.

Photons are thought to interact with light-sensitive molecules within the mitochondrial respiratory chain, with cytochrome c oxidase frequently proposed as an important photoacceptor. The resulting cellular signalling may influence processes involving ATP production, reactive oxygen species, nitric oxide and downstream signalling pathways.

Ultimately, these responses may affect processes including inflammation, tissue repair and cellular proliferation. That’s very different from the idea that red light simply “warms up the skin”.

But understanding a plausible biological mechanism is only part of the story.

The important question is:

Does it produce clinically meaningful results?

What about skin rejuvenation?

This is where red light therapy becomes particularly interesting to aesthetic practitioners.

Studies of photobiomodulation have reported changes associated with skin rejuvenation, including improvements in measures such as skin texture, fine lines and collagen-related processes. There is therefore reasonable scientific justification for continued interest in PBM as a non-invasive approach to supporting skin quality.

However, there’s an important distinction between saying:

“There is evidence supporting photobiomodulation.”

and:

“Any device containing red LEDs will rejuvenate the skin.”

Those are not the same statement.

The problem with the words “red light”

Imagine discussing an injectable treatment but knowing only that the syringe contains “a liquid”. You’d want to know considerably more before deciding whether it was appropriate.

The same principle applies here. When assessing a PBM device or published study, some of the important variables include:

• Wavelength
  What wavelengths are actually being delivered?
• Irradiance
  How much optical power is reaching a given area of tissue?
• Dose or fluence
  How much energy is ultimately delivered over the treatment period?
• Treatment duration
  How long is the tissue exposed?
• Distance from the skin
  This can materially affect the amount of energy reaching the target.
• Treatment frequency
  Once a month and several times a week are very different protocols.
• Device design and coverage
  Is the intended treatment area receiving a reasonably consistent dose?

Suddenly, comparing two products because they both produce a red glow doesn’t seem particularly useful.

More isn’t necessarily better

There’s another interesting feature of photobiomodulation.

The relationship between dose and biological effect isn’t necessarily a simple case of more energy = better result.

PBM research frequently discusses a biphasic dose response, where an appropriate dose may produce a beneficial biological response while increasing exposure beyond that range doesn’t necessarily increase the benefit and may potentially reduce it.

That makes treatment parameters particularly important. It also makes statements such as “our device is more powerful” considerably less informative without knowing how that power translates into the actual treatment protocol.

Professional device versus £100 home mask?

This is probably where the discussion gets most interesting.

A consumer device isn’t automatically ineffective because it costs less. Likewise, an expensive professional device isn’t automatically effective because it sits in a clinic and has an impressive control panel.

The better questions are:

• What wavelength does it deliver?
• At what irradiance?
• What dose reaches the treatment area?
• What protocol is recommended?
• What evidence supports that particular device or treatment parameters?
  And are the marketing claims consistent with that evidence?
• Those questions tell you considerably more than the price tag.

Where could it fit within an aesthetic clinic?

Perhaps the most interesting role for PBM isn’t as a trending standalone treatment. It may be as part of a broader skin-health or treatment protocol.

Its non-invasive nature makes it particularly interesting when considering approaches centred around skin quality, recovery and complementary treatment strategies.

That also changes how it should potentially be presented to patients. Rather than promising dramatic transformation from sitting beneath a light, the more credible discussion may be about where PBM can support a wider treatment plan and where the available evidence justifies its use.

So… worth the hype?

THE TELETA VERDICT: PROMISING — WITH CAVEATS.

There is credible biological science behind photobiomodulation, and a growing body of research examining its application to skin and other tissues.

So we’d struggle to dismiss red light therapy as simply another social-media fad. But we’d be equally cautious about accepting every claim made for every red light device.

The effectiveness of PBM depends on considerably more than whether a device glows red.

• Wavelength matters.
• Dose matters.
• Irradiance matters.
• Treatment protocol matters.
• And evidence matters.

So perhaps the question practitioners should be asking isn’t:

“Does red light therapy work?”

It’s:

“What exactly is this device delivering — and is there good evidence that those parameters produce the outcome I’m trying to achieve?”

That’s a much harder question for a manufacturer to answer. And probably a much better one for a practitioner to ask.

Worth the Hype? — from Teleta

Every month we’ll take a closer look at a treatment, technology or trend generating conversation in aesthetics — separating interesting science from interesting marketing.

What should we investigate next? Let us know.

This article is intended for healthcare and aesthetics professionals for general educational purposes. It does not constitute medical advice or a recommendation of any particular device, treatment or treatment protocol.