Red or infrared? Most panels list both, and most people can't say what the difference is. Here is what the published research says about how the two wavelength ranges differ, and where the evidence is still thin.
Study at a glance
- Source 1: Hamblin MR. "Mechanisms and applications of the anti-inflammatory effects of photobiomodulation." AIMS Biophysics, 2017;4(3):337–361 (peer-reviewed review).
- Source 2: Giménez et al. "Effects of Near-Infrared Light on Well-Being and Health in Human Subjects with Mild Sleep-Related Complaints: A Double-Blind, Randomized, Placebo-Controlled Study." Biology, 2023;12(1):60.
- Source 3: Batista et al. "Immediate effects of red (660 nm) and infrared (808 nm) photobiomodulation therapy on fatigue of the orbicularis oris muscle: a randomized clinical study." CoDAS, 2021;34(2):e20200363 (60 women, ages 19–43).
What the research shows
"Photobiomodulation" is the research term for using red and near-infrared light to influence cells. Hamblin's review describes the main light-sensitive target as cytochrome c oxidase, an enzyme in the mitochondria. It absorbs light in both the red range (around 660 nm) and the near-infrared range (roughly 810–830 nm).
The same literature describes a practical difference in depth. Red light is considered best suited to superficial tissue, such as the skin. Near-infrared light penetrates more deeply, with penetration described as greatest around 810 nm. At longer wavelengths, water absorbs more of the light and penetration falls again.
In human trials, near-infrared has been studied for well-being outcomes. Giménez and colleagues ran a double-blind, randomized, placebo-controlled study of 850 nm light in people with mild sleep-related complaints. According to published summaries, they reported improvements in mood, drowsiness and resting heart rate at a dose of 6.5 J/cm². This is one study in a specific group, so it is not proof of a general effect.
Results are not uniformly positive. Batista and colleagues compared 660 nm and 808 nm laser light on lip-muscle fatigue in 60 women. They found no significant difference before and after irradiation, and concluded that the parameters tested had no immediate effect. Dose, timing, target tissue and device all matter, and results from one setup do not transfer neatly to another.
Why it may work
The proposed mechanism is that photons absorbed by mitochondrial enzymes may change cellular energy metabolism and signaling. Because red light is absorbed nearer the surface and near-infrared reaches deeper, the two are often thought of as complementary: red for the surface, infrared for deeper layers. This is a working hypothesis, and researchers are still refining the optimal parameters.
Real-world use
People typically use red and near-infrared light in short, regular sessions, often in the evening or after training. Whether a given routine does anything for you is individual. Treat it as a wellness habit rather than a medical intervention.
Where Gudslip fits in
The Red & Infrared Light Therapy Panel combines both wavelength ranges in one device, so you can use the red and near-infrared light the research discusses. It is a wellness device. It is not designed to diagnose, treat or cure any condition, and it has not been shown to reproduce the results of the studies above.
How to use it
- Follow the manufacturer's instructions for distance and session length.
- Use clean, bare skin and protect your eyes as directed.
- Start with short sessions and stay consistent for several weeks before judging.
- Stop if you notice discomfort, and speak to a professional if you are unsure whether it suits you.
FAQ
Is infrared "stronger" than red? Not exactly. They differ mainly in how deeply they penetrate, not in being stronger or weaker.
Do I need both? Research uses both, and some devices combine them. There is no firm evidence that one is always better.
Does the heat I feel mean it is working? Near-infrared can feel mildly warm, but warmth is not a measure of effect.
Can it replace medical care? No. It is a wellness tool and does not replace professional advice.
The bottom line
Red light is generally considered to act nearer the surface and near-infrared deeper. Mechanistic research is encouraging, but human trials are mixed and depend heavily on dose and design. Set realistic expectations and use it as one part of a healthy routine.
Disclaimer: This article is for general wellness information only and is not medical advice. Gudslip products are not intended to diagnose, treat, cure or prevent any disease. Consult a healthcare professional before starting any new routine, especially if you are pregnant, have a medical condition or take photosensitizing medication.
References
- Hamblin MR. Mechanisms and applications of the anti-inflammatory effects of photobiomodulation. AIMS Biophysics. 2017;4(3):337–361. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5523874/
- Giménez et al. Effects of Near-Infrared Light on Well-Being and Health in Human Subjects with Mild Sleep-Related Complaints: A Double-Blind, Randomized, Placebo-Controlled Study. Biology. 2023;12(1):60. https://www.mdpi.com/2079-7737/12/1/60
- Batista MR, Estrela LA, Alves VMN, Motta AR, Furlan RMM. Immediate effects of red (660 nm) and infrared (808 nm) photobiomodulation therapy on fatigue of the orbicularis oris muscle: a randomized clinical study. CoDAS. 2021;34(2):e20200363. https://pubmed.ncbi.nlm.nih.gov/34705999/