🔗 Share this article

Light therapy is certainly having a moment. Consumers can purchase light-emitting tools designed to address complexion problems and aging signs along with muscle pain and periodontal issues, the newest innovation is a toothbrush enhanced with miniature red light sources, promoted by the creators as “a significant discovery in personal mouth health.” Internationally, the market was worth $1bn in 2024 and is projected to grow to $1.8bn by 2035. Options include full-body infrared sauna sessions, which use infrared light to warm the body directly, the infrared radiation heats your body itself. Based on supporter testimonials, it feels similar to a full-body light therapy session, stimulating skin elasticity, soothing sore muscles, reducing swelling and persistent medical issues as well as supporting brain health.

Understanding the Evidence

“It sounds a bit like witchcraft,” says a Durham University professor, a scientist who has studied phototherapy extensively. Certainly, we know light influences biological functions. Sunlight helps us make vitamin D, needed for bone health, immunity, muscles and more. Light exposure controls our sleep-wake cycles, too, stimulating neurotransmitter and hormone production during daytime, and signaling the body to slow down for nighttime. Artificial sun lamps frequently help individuals with seasonal depression to combat seasonal emotional slumps. So there’s no doubt we need light energy to function well.

Different Light Modalities

While Sad lamps tend to use a mixture of light frequencies from the blue end of the spectrum, the majority of phototherapy tools use red or near-infrared wavelengths. In rigorous scientific studies, such as Chazot’s investigations into the effects of infrared on brain cells, finding the right frequency is key. Light is a form of electromagnetic radiation, which runs the spectrum from the lowest-energy, longest wavelengths (radio waves) to short-wavelength gamma rays. Phototherapy, or light therapy uses wavelengths around the middle of this spectrum, including invisible ultraviolet radiation, followed by visible light encompassing rainbow colors and infrared light visible through night vision technology.

Ultraviolet treatment has been employed by skin specialists for decades to manage persistent skin disorders including eczema and psoriasis. It affects cellular immune responses, “and suppresses swelling,” says Dr Bernard Ho. “Substantial research supports light therapy.” UVA goes deeper into the skin than UVB, while the LEDs in consumer devices (usually producing colored light emissions) “typically have shallower penetration.”

Safety Considerations and Medical Oversight

UVB radiation effects, such as burning or tanning, are understood but clinical devices employ restricted wavelength ranges – meaning smaller wavelengths – which minimises the risks. “Treatment is monitored by medical staff, so the dosage is monitored,” explains the dermatologist. And crucially, the devices are tuned by qualified personnel, “to confirm suitable light frequency output – different from beauty salons, where regulations may be lax, and emission spectra aren’t confirmed.”

Home Devices and Scientific Uncertainty

Colored light diodes, he notes, “aren’t typically employed clinically, though they might benefit some issues.” Red light devices, some suggest, help boost blood circulation, oxygen uptake and cell renewal in the skin, and activate collagen formation – a primary objective in youth preservation. “Studies are available,” states the dermatologist. “But it’s not conclusive.” In any case, with numerous products on the market, “it’s unclear if device outputs match study parameters. Appropriate exposure periods aren’t established, proper positioning requirements, whether or not that will increase the risk versus the benefit. There are lots of questions.”

Treatment Areas and Specialist Views

One of the earliest blue-light products targeted Cutibacterium acnes, microorganisms connected to breakouts. Research support isn’t sufficient for standard medical recommendation – despite the fact that, says Ho, “it’s commonly used in cosmetic clinics.” Some of his patients use it as part of their routine, he says, though when purchasing home devices, “we recommend careful testing and security confirmation. Unless it’s a medical device, standards are somewhat unclear.”

Advanced Research and Cellular Mechanisms

Simultaneously, in a far-flung field of pioneering medical science, scientists have been studying cerebral tissue, identifying a number of ways in which infrared can boost cellular health. “Pretty much everything I did with the light at that particular wavelength was positive and protective,” he states. The numerous reported benefits have generated doubt regarding phototherapy – that it’s too good to be true. But his research has thoroughly changed his mind in that respect.

The researcher primarily focuses on pharmaceutical solutions for brain disorders, however two decades past, a physician creating light-based cold sore therapy requested his biological knowledge. “He developed equipment for cellular and insect experiments,” he says. “I remained doubtful. This particular frequency was around 1070 nanometers, which most thought had no biological effect.”

Its beneficial characteristic, nevertheless, was its efficient water penetration, meaning it could penetrate the body more deeply.

Mitochondrial Effects and Brain Health

More evidence was emerging at the time that infrared light targeted the mitochondria in cells. Mitochondria produce ATP for cell function, generating energy for them to function. “All human cells contain mitochondria, particularly in neural cells,” says Chazot, who prioritized neurological investigations. “It has been shown that in humans this light therapy increases blood flow into the brain, which is consistently beneficial.”

With 1070 treatment, cellular power plants create limited oxidative molecules. At controlled levels these compounds, notes the scientist, “triggers guardian proteins that maintain organelle health, protect cellular integrity and manage defective proteins.”

All of these mechanisms appear promising for treating a brain disease: oxidative protection, anti-inflammatory, and cellular cleanup – autophagy representing cellular waste disposal.

Current Research Status and Professional Opinions

When recently reviewing 1070nm research for cognitive decline, he says, approximately 400 participants enrolled in multiple trials, comprising his early research projects