Can You Use Any Red Light for Red Light Therapy? What Counts
Can you use any red light for red light therapy? Not with confidence: study results come from light with a stated wavelength band and a measured output at a stated distance, and an ordinary red bulb, LED strip or heat lamp is made for colour or warmth, not for that. The source matters less: lamps, LEDs and lasers have all produced results when the band and dose were known. Below: how common red lights compare, what studies used, and how to read a spec sheet.
Key takeaways
- Dermatology researchers define red light as 620 to 700 nm and near-infrared light as 700 to 1,440 nm. Maghfour, 2024
- A 2026 review puts typical irradiance in skin studies at 20 to 60 mW/cm² and typical doses at 4 to 18 J/cm². Spongberg, 2026
- In a 2014 controlled trial using fluorescent tubes, 69% of the red light group had better blinded wrinkle ratings after 30 sessions, against 4% of untreated controls. Wunsch, 2014
- A 2018 review concluded that lasers "could indeed be replaced by LEDs without significant worsening of the results". Heiskanen and Hamblin, 2018
- Lumens on a bulb box are weighted to the eye's sensitivity, which peaks at 555 nm, so a lumen figure cannot tell you a therapy dose. NIST
What makes red light "therapeutic" rather than just red?
Three things: a stated wavelength band, a measured output at a stated distance, and a session time. Together they give the dose, which is how studies describe the light they used.
A 2026 product guide in Cureus says "Reputable companies will clearly list the wavelengths used". Spongberg, 2026 It adds that devices without irradiance or dose figures "may operate outside the therapeutic range".
| What matters | How a study describes it | How a household red bulb box describes it |
|---|---|---|
| Wavelength | A band in nm, such as 630 ± 10 nm | A colour name, such as "red" |
| Output | mW/cm² at a stated distance | Lumens and watts |
| Time | Minutes per session, sessions per week, number of weeks | Not given, as the bulb is made for lighting |
| Light type | Red, near-infrared or both, named separately | Visible colour only |
The research name is photobiomodulation. A 2025 expert consensus from a 21-member panel found it appears safe for adults. Maghfour, 2025 The same group notes that outcomes depend on dose, treatment time and output power. Maghfour, 2024 Colour alone tells you none of those.
Can you use any red light for red light therapy, whatever the wavelength?
No single number is required, but the light should fall in the bands with research behind them: about 600 to 700 nm for red and 770 to 1,200 nm for near-infrared. Light between about 700 and 770 nm has a weaker track record.
A 2017 review found that red and near-infrared in those bands have "shown positive results". Hamblin, 2017 For 700 to 770 nm, it says "the results are likely to be disappointing".
The red does not have to be exactly 660 nm. Published studies have used 633 nm LEDs, 611 to 650 nm fluorescent tubes and a 630 ± 10 nm LED mask. Our guide to 630 nm vs 660 nm red light explains why neither has been shown to beat the other.
LED emission is "typically some tens of nanometers" wide, so a 660 nm LED covers a spread of red around its peak. RP Photonics For the full map of bands, see our red light therapy wavelength chart.
Can a regular red light bulb or red night light be used for red light therapy?
A red filament bulb gives red-looking light, but it is made for colour and states no output in the red band. A red night light is a lighting choice for the evening, not a skin dose.
Incandescent and halogen lamps "are based on electrical resistive heating", unlike LEDs. Heiskanen and Hamblin, 2018 Most of what a filament bulb gives off is heat and near-infrared.
Our guide to red light therapy bulbs estimates that roughly 1 to 2% of an incandescent bulb's radiated energy falls in the 600 to 700 nm band. Red household LED bulbs give real red light, but at room-lighting strength. Purpose-made LED therapy bulbs exist, and they can only be judged when the maker states the output at a distance.
Is an infrared heat lamp the same as red light therapy?
No. A heat lamp is built to warm you, while a red light therapy device is built to deliver light at a stated wavelength and output.
Incandescent heat lamps carry a known burn and fire risk. The precautions in our bulbs guide include keeping the lamp 15 to 20 inches from the skin, a ceramic socket, a guard and at least 18 inches of clearance from cloth and paper. Never leave one on unattended, and avoid it if you have reduced sensation or might doze off.
Repeated radiant heat can also mark the skin. DermNet describes erythema ab igne, a net-like red rash, as caused by "chronic exposure to infrared radiation in the form of heat". DermNet See infrared heat lamp vs red light therapy.
Do red LED strips or colour-changing smart bulbs work for red light therapy?
They make real red light, but they are sold for colour and brightness, with no wavelength band or output at a distance on the box. They are also made to be seen, so they are not designed to emit near-infrared.
This is where the question "can any red light be used for red light therapy" comes up most. Colour-changing lamps create their colours by mixing red, green and blue LEDs. RP Photonics Choosing "red" switches on the red channel, at a brightness set for a room.
The box names a colour rather than a peak in nm, and gives no output at skin distance. Without those, there is no way to know how long a session should last.
Why don't lumens or watts on the box tell you the dose?
Lumens measure brightness as the human eye sees it, and watts measure electricity drawn from the wall. Studies describe light in mW/cm² at a stated distance, which neither figure gives you.
Lumens weight light by the eye's sensitivity across 360 to 830 nm, a curve "normalized to unity at its peak, 555 nm". NIST Deep red counts for little in a lumen figure, and 850 nm near-infrared sits outside the curve altogether.
A typical LED turns only 20 to 30% of its electricity into light. Heiskanen and Hamblin, 2018
Irradiance is the figure that matters, and 10 W/m² equals 1 mW/cm². A 2016 review of 74 light therapy papers found that 54 of them (73%) gave no measurement method and relied on the maker's stated values. Hadis, 2016 Our guide to the strongest red light therapy at home explains irradiance further.
Can you hold a red torch against your skin instead of using a panel?
A small torch lights a small patch, and that patch widens and thins quickly as you move the torch away. Without a stated output, you cannot tell how long to hold it.
A 2025 bench test of handheld LED devices showed the geometry. Cronshaw, 2025 For a device 3 cm across, the lit area grew from about 7 cm² near contact to about 28 cm² at 2 cm and about 154 cm² at 7.5 cm.
The same light spread over more than 20 times the area gives far less per square centimetre, which is why output only means something with a distance attached.
Does the light have to come from a laser, or do LEDs and lamps count?
LEDs and lamps both count: the band and the dose matter more than the source. Reviews comparing lasers with matched non-laser light found little difference.
A 2017 review states that "non-coherent light-emitting diodes (LEDs) work equally well". Hamblin, 2017 The 2018 review of about 40 comparison papers notes that diode lasers are 1 to 2 nm wide and LEDs broader. It concluded that "LED photobiomodulation is here to stay".
The 2014 trial used lamps. Wunsch, 2014 One group sat under fluorescent tubes peaking at 611 to 650 nm. Another used gas-discharge lamps filtered to a broad 570 to 850 nm. Sessions delivered 8.5 to 9.6 J/cm² in the red band, twice a week, for 30 sessions.
- Wrinkles: blinded ratings were better in 69% of the red group, 75% of the broad-band group and 4% of untreated controls.
- Broad vs narrow: the authors found "no advantage over the red-light-only spectrum" for the broad lamps.
The controls were untreated volunteers rather than a sham group. These were purpose-built lamps with measured output: the results followed a stated band and dose, not a bulb's colour.
Do you need near-infrared as well as visible red light?
Both have trial support, and they reach different depths. In a sham-controlled trial, red alone, near-infrared alone and both together each improved wrinkles.
The split-face trial gave 76 people 830 nm LED light, 633 nm, both, or sham, twice a week for 4 weeks. Lee, 2007 Wrinkles fell by up to 36% and elasticity rose by up to 19% in the active groups. The light was "well-tolerated by all patients".
Red alone can also help skin. In a 2023 study of 20 adults using a red-only 630 ± 10 nm LED mask, crow's feet depth fell by 38.3% at 12 weeks, though there was no control group. Couturaud, 2023
Near-infrared reaches further than red, which is why it is chosen for joints and muscles. Near-infrared is invisible, so a device can look dim while it works, and eye protection still matters: see red light therapy goggles.
What settings did the red light studies use?
Skin studies mostly used red or near-infrared light at modest irradiance, for about 10 to 25 minutes, twice a week, over 4 to 12 weeks. Brighter is not automatically better.
| Study | Light source | Wavelength | Irradiance | Dose per session | Minutes | Schedule |
|---|---|---|---|---|---|---|
| Wunsch, 2014 (controlled, no sham) | Fluorescent tubes; filtered gas-discharge lamps | 611 to 650 nm; broad 570 to 850 nm | 5.9 to 13.3 mW/cm² (red band) | 8.5 to 9.6 J/cm² | 12 to 25 | Twice a week, 30 sessions |
| Couturaud, 2023 (no control group) | LED mask | 630 ± 10 nm | 21.7 mW/cm² | 15.6 J/cm² | 12 | Twice a week, 3 months |
| Spongberg, 2026 (review of skin studies) | LED masks | About 630 to 660 nm and 830 to 850 nm | 20 to 60 mW/cm² | 4 to 18 J/cm² | About 10 to 12 | Twice a week, about 4 to 12 weeks |
Light research describes a biphasic dose response, mostly from cell and animal work: beyond an optimum, more energy can reduce the effect. Huang, 2009 The practical lesson is to follow a device's stated settings and build up gradually, rather than chase the brightest light.
How do the Kivorla panel and mask measure up to this checklist?
Both state their wavelengths in nm and their output, so you can check them against the research bands. Their red and near-infrared wavelengths sit inside those bands.
Whatever device you look at, check for:
- Wavelengths in nm: red of about 630 to 660 nm and near-infrared of about 830 to 850 nm are the most studied. Spongberg, 2026
- Output at a stated distance: mW/cm² or W/m², not watts or LED count.
- Eye protection: the AAD advises wearing it every time and following the directions exactly. AAD
- Independent testing: a dermatologist quoted by NPR suggests looking for third-party testing of wavelength and irradiance. NPR, 2026
| Spec-sheet line | 9-Spectrum Panel | 4-Wavelength Mask |
|---|---|---|
| Wavelengths | 480, 590, 630, 660, 670, 810, 830, 850 and 1060 nm | 665 nm red; 850 and 1064 nm near-infrared; 460 nm blue |
| Stated output | At least 1,567 W/m² at 6 inches (near-infrared at least 1,200, red at least 150) | 50 to 103 mW/cm² |
| Output control | Each wavelength dimmable from 1 to 100% | Brightness 50, 70 or 90% |
| Timer | 1 to 30 minutes; stops at 5 minutes if no time is set | 5, 10 or 15 minutes; switches off when the timer ends |
The 9-Spectrum Red Light Therapy Panel is for body areas. Hang it on a door or wall with the included door hook and pulley, or stand it upright on the floor. Put the goggles on before switching on and keep your eyes closed.
- Distance: about 6 inches for a joint, about 12 inches for a broad area such as the back.
- Time: 10 to 15 minutes per area, with at least 6 hours between 30-minute sessions.
- Staying near the studied range: dim each wavelength on the controller, set a shorter timer (it starts at 1 minute), or step back towards 12 inches.
- Warmth: the surface stays at or below 40°C; if skin feels too warm, move back or stop.
For the face, use the 4-Wavelength Red Light Therapy Mask. It uses VCSEL laser diodes, and its red mode combines 665 nm red with 850 and 1064 nm near-infrared. The blue mode pairs 460 nm blue with 850 nm. It is cordless, with a handheld controller or voice control.
- Start: on clean, dry skin at 50% brightness on the 10-minute timer, then 70 or 90% if your skin stays calm.
- Weekly limits: 10-minute sessions up to 4 times a week at high brightness, or 15-minute sessions up to 3 times a week after a build-up week of three 10-minute sessions.
- Daily cap: 20 minutes, and do not stare into the light.
The AAD notes darker skin can be more sensitive to visible light, and the panel is not for Fitzpatrick skin types V or VI. Our precautions rule out use during pregnancy, with epilepsy, with a thyroid condition or over broken skin. They also rule out photosensitising medication, so anyone taking a medicine should check with their pharmacist or doctor first.
Read the precautions before ordering. Standard shipping to the US, UK and Germany is free. Under our return and refund policy, returns are accepted within 30 days: an unopened device with its seals intact is refunded less a 10% restocking fee, and an opened device that is undamaged and complete is refunded less 20%.
Kivorla devices are general wellness devices, not medical devices, and are not intended to treat any condition. If you have a light-sensitive skin condition or take medicines that affect light sensitivity, speak to a doctor or dermatologist before using any red light device.