Red Light Therapy,
explained.

Also called photobiomodulation, which is the word you will see in the research.

Specific shades of red and near infrared light are absorbed inside your cells and nudge their energy production. The goal is not heat, tanning or making skin look red: it is delivering a measured dose of light the body can use.

The important part is consistency. Red light is not usually about one dramatic session. It works best as a regular routine at a sensible dose, which is why the important questions are wavelength, power at the skin, time and distance rather than how bright a device looks.

Where it is used

Skin and visible ageing, muscle recovery and joint comfort, and a wider researched field reaching brain, sleep and vision. The evidence ranges from randomised trials and meta-analyses to early studies, and it is laid out on the clinical studies page.

The wavelength decides how deep the signal travels.

Red, the surface

You can see it, and it works where you can see: skin quality, surface circulation, collagen-supportive routines, visible ageing goals, scalp and hair.

Near infrared, deeper

Mostly invisible, and it travels further, into muscle, joints and soft tissue. This is the waveband discussed around recovery and performance.

Deeper than you would think

Professor Glen Jeffery’s lab at UCL has shown long-wavelength light passes through skin and even bone, scattering through the body. In his experiments it also passed through several layers of clothing, whatever the colour, and through closed eyelids. Effects can be systemic, not just where the light lands. Red and near infrared are usually used together: red for the surface, near infrared for depth.

Five mechanisms, in plain English. Why light may help, not a promise that it will.

1. 1

   The light receiver

   Red and near infrared light is absorbed by cytochrome c oxidase, the main light receiver inside your mitochondria. That is the doorway for everything else.

   Professor Glen Jeffery’s own view is that much of the absorption happens in the water packed around mitochondria, making it less viscous so the energy machinery turns more freely. Still being tested, and the practical result is the same: more ATP.

   What lies at the heart of photobiomodulation · Review, 2020
2. 2

   More cellular energy

   The nudge helps cells make more ATP, their fuel. With more available energy, normal repair and recovery run more efficiently.

   Powner & Jeffery · Journal of Biophotonics, 2024
3. 3

   Blood flow

   Light supports circulation through nitric oxide, a signalling molecule involved in blood flow and mitochondrial function.

   Hamblin · BBA Clinical, 2016
4. 4

   Calmer inflammation

   Some inflammation is part of healing, but too much for too long slows recovery. Photobiomodulation is studied for settling an over-active recovery environment.

   Hamblin · AIMS Biophysics, 2017
5. 5

   Skin’s scaffolding

   In a randomised controlled trial, red and near infrared light measurably increased intradermal collagen density and improved skin appearance.

   Wunsch & Matuschka · Photomedicine and Laser Surgery, 2014

Mechanisms describe biology being researched, not a promise of individual results or a treatment claim.

The same handful of cellular effects, in different combinations.

• Anti-ageing & beauty

  Collagen density, skin tone and texture, measured in randomised trials. The scaffolding biology under skin quality.

  Main mechanisms: collagen synthesis · circulation · calmer inflammation

• Recovery & discomfort

  Meta-analyses report benefits for knee osteoarthritis pain and neck pain, including one in The Lancet.

  Main mechanisms: calmer inflammation · circulation · cellular energy

• Sports recovery & performance

  Studied for muscular performance and reduced fatigue across systematic reviews of randomised trials.

  Main mechanisms: mitochondrial ATP · muscle oxygenation · calmer inflammation

• Longevity & brain health

  Transcranial trials report cognition and BDNF gains in adults over 50. A young field, presented as research.

  Main mechanisms: cellular energy · circulation · calmer inflammation

• Sleep

  A controlled trial in athletes reported better sleep quality and melatonin after evening red light. Small, but real.

  Main mechanisms: circadian signalling · nervous-system settling

The research we follow, with the man leading it

Several of these findings come from Professor Glen Jeffery’s lab at UCL, whose research programme we support: a 15 minute dose of red light lowering a blood sugar spike by around 28%, and long wavelengths passing through skin, clothing and even bone. The gains are clearest from around 40, when ageing mitochondria have the most room to recover.

Calm and simple, and mostly about showing up.

When to do it

Timing matters more than most people expect. In Professor Jeffery’s vision trials, morning doses, before about 11am, produced the improvement, and the same dose in the afternoon did nothing. So we talk about when you use it, not just how long.

No. That is why we screen first, always.

Red light is non-invasive and considered low risk used sensibly. It still is not for every person in every situation.

When we say the clinician route first

• Photosensitive conditions such as lupus or porphyria
• Photosensitising medications, including some antibiotics, acne and psychiatric medications
• Pregnancy, especially full-body use
• Active or suspected cancer, unless your clinical team advises otherwise

Eyes stay covered for full-body and face work. We ask the safety questions on every call, before anything progresses.

The right format depends on your goal, space and routine.

What actually sets the dose

Six things: wavelength, the power actually reaching your skin, time, distance, coverage and frequency. Brightness is not one of them, and quality is verified dose rather than LED count.

One more thing from the research: the effect behaves like a switch rather than a dial. The published vision trials used about 8 milliwatts per square centimetre, a modest level, and once the dose is delivered, extra light adds nothing.

Shaped with the research

Our light systems are shaped with Professor Glen Jeffery at UCL, and we deliver and set up every system ourselves.

A sensible dose, repeated, beats occasional intensity.

Ten to twenty minutes, three to five times a week, at the distance the protocol sets. Morning doses tend to land best in the research, and a machine at home removes the travel, which is what usually breaks the habit.

A short dose also lasts longer than you would guess: in the vision trials, one three minute morning exposure held for about a week. Protocols differ by goal, so we set the rhythm with you.

One more thing about light

Professor Jeffery also points out that modern LED lighting spikes hard in the blue and carries almost none of the balancing red and near infrared we evolved under. Older incandescent and halogen bulbs sit much closer to that balance. Using light well means thinking about your whole lighting environment, not only the sessions.