Red light therapy is everywhere — from dermatology clinics to at-home LED masks. But what can it actually do for your skin? We look at the science behind the red glow, from collagen and fine lines to how it works and what to know before adding it to your routine.
You've probably seen it by now: red LED masks, glowing panels and people spending ten minutes of their evening bathed in red light.
Red light therapy has become one of the more talked-about practices in beauty and wellness. And while some of the claims surrounding it get ahead of the science, the treatment itself isn't simply another passing trend.
Known scientifically as photobiomodulation (PBM), red light therapy uses specific wavelengths of red and near-infrared light to influence biological processes within our cells. Unlike UV light, it doesn't work by damaging the skin. Instead, certain wavelengths of light appear to interact with cellular processes involved in energy production, signalling and tissue repair. [1,2]
And one area where the evidence is particularly interesting? Skin and collagen.
First things first: what is red light therapy?
Red light therapy exposes the skin to low levels of red or near-infrared light, usually through LEDs or low-level lasers.
The exact wavelengths vary between devices and studies. Red light is generally in the visible spectrum, while near-infrared light has a longer wavelength and can penetrate more deeply into tissue.
The important distinction is that this isn't UV light. Red and near-infrared light behave differently from the ultraviolet radiation we're exposed to from the sun. Short-term studies suggest that red light therapy is generally well tolerated when used appropriately, although we still don't have all the answers about very long-term, frequent at-home use. [3]
So how can light actually affect the skin?
This is where it gets interesting. One of the main theories involves the mitochondria — the structures inside our cells responsible for producing much of the energy those cells need. Red and near-infrared photons appear to interact with light-sensitive components within cells, influencing mitochondrial activity and cellular signalling. This can affect processes involved in energy production, inflammation, circulation and tissue repair. [1,2]
Put much more simply: red light doesn't put collagen into your skin. It appears to influence the cells and signals involved in maintaining and repairing it. And that brings us to collagen.
What does the research say about collagen?
Collagen is one of the major structural proteins in our skin. It helps give the dermis its structure and strength, but both collagen production and the organisation of existing collagen change as we age. Several human studies suggest that photobiomodulation may influence collagen and improve certain visible signs of skin ageing.
In one controlled clinical trial involving 136 participants, researchers compared different red and near-infrared light treatments with a control group. After 30 sessions, the treated groups showed improvements in skin roughness and complexion as well as a measurable increase in intradermal collagen density. [4]
That last point is particularly interesting: researchers weren't only asking participants whether they thought their skin looked better. Collagen density was measured using ultrasound. [4]
Another randomized clinical trial looked at 137 women between 40 and 65 years old. After ten sessions over four weeks, red light at 660 nm reduced measured wrinkle volume around the eyes by 31.6%. [5]
But there's an important detail. The same study did not find significant improvements in skin hydration or viscoelasticity. [5] Which is a useful reminder of how we like to look at research: a study can show something interesting without proving everything.
So, does red light “boost collagen”?
It's tempting to reduce the answer to a yes or no. The reality is more nuanced. Laboratory and clinical research suggests that photobiomodulation can influence fibroblast activity, collagen-related processes and the extracellular matrix. Human trials have also measured increases in collagen density and improvements in certain signs of photoageing. [2,4]
That's meaningful. But studies use different wavelengths, intensities, treatment schedules and devices, which makes it difficult to turn the research into one universal promise. A systematic review of randomized controlled trials in dermatology highlighted encouraging results while also noting limitations including small sample sizes, differences in treatment parameters and a lack of blinding or sham controls in some studies. [6]
So we'd describe the evidence as promising rather than magical.
The detail that matters more than you might think: dose
Not all red light is the same.
Wavelength matters. So does intensity. Distance from the light matters. Treatment time matters. And how often you use it matters. Photobiomodulation depends on the amount of light that actually reaches the tissue, which means a more powerful device or a longer session isn't automatically better. This is also why comparing two LED masks based only on the number of LEDs — or how bright they look — doesn't tell you very much. The useful question is whether a device delivers an appropriate wavelength and dose for the purpose it's designed for.
How often should you use it?
There's no single schedule that applies to every red-light device. Clinical studies use different protocols. The 137-woman study above used ten sessions over four weeks, while the 136-participant study used treatment twice weekly for 30 sessions. [4,5]
For an at-home device, the sensible approach is much simpler: follow the protocol designed and tested for that particular device. Don't assume doubling the treatment time will double the result. And think in terms of consistency rather than instant transformation. The studies looking at changes in skin structure generally measure results over weeks or months — not after one ten-minute session.
What should you look for in an at-home device?
The red-light mask that looks best on your bathroom shelf isn't necessarily the one with the best evidence behind it.
A few things are worth checking:
- Wavelengths: The manufacturer should clearly state which wavelengths the device emits.
- Treatment protocol: How long should you use it, and how often?
- Dose: Look for information about irradiance or energy delivered rather than simply how many LEDs the device contains.
- Evidence: Has the actual device been studied, or is the brand relying on general research about red light?
- Eye safety: Follow the manufacturer's instructions about eye protection.
Where does red light fit into a skin routine?
Perhaps the best way to think about red light therapy is as one tool, not the whole toolbox.
It doesn't replace sunscreen. It doesn't cancel out excessive UV exposure. And it doesn't replace the fundamentals that support normal skin function — including adequate nutrition, protein and the micronutrients involved in collagen formation.
But alongside those fundamentals, the research into photobiomodulation is genuinely interesting.
We now have human studies showing measurable changes in collagen density and certain measurements of wrinkles and skin texture. At the same time, researchers are still working out the optimal wavelengths, doses and treatment schedules. [4–6]
So, is red light therapy worth the hype?
Potentially — as long as the expectations stay grounded.
Think of it less as a beauty hack and more as a long-term practice. Choose a well-designed device, use it consistently and correctly, and give your skin time.
Because, as with most things related to skin, the less exciting answer is often the more useful one: Consistency tends to matter more than quick fixes.
References
- Hamblin MR. Mechanisms and applications of the anti-inflammatory effects of photobiomodulation. AIMS Biophysics, 2017.
Read the study - Khalifian S, Shisler J. Photobiomodulation and Biological Pathways in Skin Regeneration and Rejuvenation: Light and Biological Activation of Skin Improvement. Facial Plastic Surgery Clinics of North America, 2026.
Read the review - American Academy of Dermatology. Is red light therapy right for your skin?
Read the guidance - Wunsch A, Matuschka K. A Controlled Trial to Determine the Efficacy of Red and Near-Infrared Light Treatment in Patient Satisfaction, Reduction of Fine Lines, Wrinkles, Skin Roughness, and Intradermal Collagen Density Increase. Photomedicine and Laser Surgery, 2014.
Read the study - Mota LR, et al. Photobiomodulation Reduces Periocular Wrinkle Volume by 30%: A Randomized Controlled Trial. Photobiomodulation, Photomedicine, and Laser Surgery, 2023.
Read the study - Jagdeo J, Soriano J, Brody N. Light-emitting diodes in dermatology: A systematic review of randomized controlled trials. Lasers in Surgery and Medicine, 2018.
Read the systematic review
This article is for informational purposes only and isn't intended as medical advice. If you have a medical or skin condition, take photosensitising medication or are unsure whether red light therapy is appropriate for you, speak with a qualified healthcare professional.