Draft — pending clinical review
- This page is drafted to brief and is awaiting Forrest Smith's clinical sign-off before publication. The author byline is provisional.
Infrared light therapy is one of the most searched wellness topics online, but most guides stop at wavelength charts without explaining what the evidence actually supports. Here is what infrared light therapy does at the cellular level, which benefits are backed by research, and how it differs from red light and near infrared.
Does infrared light therapy work
The honest answer is that it depends entirely on what you are asking it to do, and the distinction matters more than most coverage of this topic admits.
For specific musculoskeletal conditions — knee osteoarthritis, chronic low back pain, tendon injury, post-surgical recovery — there is a real body of randomised controlled trial evidence, and it is summarised condition by condition further down this page. That evidence is not uniform and it is not always positive, but it exists and it is testable.
For broad general wellness claims — energy, sleep, longevity, immunity — the evidence is much weaker. Claims of that kind are common in marketing for this category and are not well supported by the clinical literature.
So the useful framing is a tiered one. Ask what condition, what tissue and what dose, and the question becomes answerable. Ask whether infrared light therapy “works” in general, and it is not really a question that has an answer.
How infrared light therapy works at the cellular level
The mechanism is the part of this field that is best understood, and it is the same regardless of which condition is being treated.
Photons in the red and near infrared range are absorbed by cytochrome c oxidase, an enzyme in the mitochondrial electron transport chain. That absorption increases electron transport activity, which raises ATP production. Downstream, this is associated with anti-inflammatory and antioxidant effects, and with changes in gene expression and cell signalling across several cell types including stem cells, fibroblasts and muscle cells.
A 2025 systematic review of 150 studies examining the molecular mechanisms of low-level laser therapy set out these gene expression and signalling pathway effects across wound healing, inflammation, cell proliferation and intervertebral disc degeneration (PMID 40131476).
Two caveats are worth stating plainly. This is a mechanism review, not a condition-specific efficacy trial, so it explains how the effect is thought to occur rather than proving any particular clinical outcome. And a plausible mechanism is not the same thing as a demonstrated benefit — which is why the condition sections below link out to the trial evidence rather than resting on the mechanism alone.
Red light vs near infrared vs infrared: what is the actual difference
This is a question of terminology rather than of clinical evidence, and it is worth being honest that the boundaries are not as fixed as most charts imply.
In broad terms, visible red light sits at the shorter end of the therapeutic range and is visible to the eye. Near infrared sits immediately beyond it, is invisible, and is the band most therapeutic devices use for deeper tissue. Infrared as a whole is a much wider region that extends well past anything used in photobiomodulation, and includes the far infrared used in saunas.
Where exactly one band ends and the next begins varies by source. There is no single agreed cut-off, and we have deliberately not cited a specific nanometre boundary as settled fact, because no strong reference supports one. Treat the ranges as a convention for talking about the spectrum, not as a clinical specification.
Why wavelength and penetration depth matter for therapeutic effect
The practical reason the distinction matters is tissue depth. Shorter red wavelengths are absorbed closer to the surface, which makes them relevant to skin. Longer near infrared wavelengths pass through more tissue before being absorbed, which is why devices built for joints and muscle are designed around that band rather than around visible red alone.
You will see specific penetration depths quoted widely — a certain number of centimetres for a certain wavelength. We are not quoting one here. The figures in circulation vary enormously and we could not find a verified source for any of them, so stating one would be presenting a guess as a measurement.
What can be said without a source problem is the direction of the relationship: longer wavelengths in this range reach deeper tissue than shorter ones, and that is the reason MOVE+ 2.0 is built around 808nm and 850nm rather than visible red on its own.
What the evidence supports, by condition
Rather than restate figures that belong on the condition pages, this section points to where each body of evidence is set out in full, along with its limitations.
- Knee and joint osteoarthritis — the largest evidence base in this category, and the one where the dose window is best characterised. See Red Light Therapy for Knee Pain and Red Light Therapy for Arthritis.
- Lower back and discogenic pain — moderate quality evidence with a clear dose dependency, and at least one well-conducted negative trial. See Red Light Therapy for Lower Back Pain and Red Light Therapy for Herniated Disc and Degenerative Disc Disease.
- Tendon and soft tissue recovery — benefit in this area is strongly wavelength dependent, and the detail matters. See Red Light Therapy for Tendonitis.
- Post-surgical recovery — a smaller but growing set of trials around knee replacement and ligament reconstruction. See Red Light Therapy for Knee Replacement Recovery and Red Light Therapy for ACL Recovery.
Infrared sauna vs infrared light therapy devices
These are different products doing different things, and the shared word in the name causes a lot of confusion.
An infrared sauna heats the whole body. The intended effect comes from the heat and from the systemic response to it. An infrared light therapy device such as MOVE+ 2.0 targets a specific area at a specific wavelength, and the intended effect is photochemical rather than thermal.
Evidence for one does not transfer to the other. If you are reading a study, check which of the two it actually tested.
Choosing the right wavelength for your goal
For surface concerns, visible red is the relevant band. For joint and muscle pain, where the target tissue sits below the surface, near infrared is the band that reaches it.
Most people asking this question want both, which is the case for a dual wavelength device. It is also worth saying that wavelength is only one of the variables — dose and consistency of use matter at least as much, and a device with the right wavelength used twice a month will not do much.
MOVE+ 2.0 and wavelength selection
MOVE+ 2.0 uses 660nm red alongside 808nm and 850nm near infrared. That combination is a design answer to the question this page has been working through: cover the surface band and the deeper band rather than choosing between them.
It is a wearable device intended for at-home use over the affected area. See the MOVE+ 2.0 product page for specifications.
Frequently asked questions
Does infrared light therapy actually work?
For specific musculoskeletal conditions there is genuine randomised controlled trial evidence, set out on the condition pages linked above. For general wellness claims the evidence is considerably weaker. The answer depends on which of those two questions you are asking.
What are the benefits of infrared light therapy?
The mechanism is well characterised — increased ATP production via cytochrome c oxidase, with downstream anti-inflammatory effects. The clinical benefits that follow from it are condition specific, and each is covered on its own page rather than summarised into a single claim here.
Is infrared therapy the same as red light therapy?
No. They are neighbouring, partly overlapping bands of the spectrum, and many devices use both. They are not interchangeable terms.
Which is better for pain relief, red light or infrared?
It depends on how deep the target tissue is. Surface tissue and deeper joint or muscle tissue are not the same problem.
Is infrared light therapy safe?
Photobiomodulation has a favourable safety profile in the clinical literature, with adverse events rarely reported. As with any therapy, anyone with a diagnosed condition or taking photosensitising medication should speak to a clinician first.
What wavelength does MOVE+ 2.0 use?
660nm red, plus 808nm and 850nm near infrared.