‘It sounds like witchcraft’: can light therapy really give you better skin, cleaner teeth, stronger joints?

Light-based treatment is certainly having a moment. Consumers can purchase light-emitting tools targeting issues like skin conditions and wrinkles along with aching tissues and oral inflammation, the latest being an oral care tool enhanced with miniature red light sources, promoted by the creators as “a breakthrough for domestic dental hygiene.” Globally, the industry reached $1 billion in 2024 and is forecast to expand to $1.8 billion by 2035. You can even go and sit in an infrared sauna, which use infrared light to warm the body directly, the thermal energy targets your tissues immediately. According to its devotees, it feels similar to a full-body light therapy session, enhancing collagen production, relaxing muscles, alleviating inflammatory responses and persistent medical issues and potentially guarding against cognitive decline.

The Science and Skepticism

“It appears somewhat mystical,” observes a Durham University professor, who has researched light therapy for two decades. Of course, some of light’s effects on our bodies are well established. Sunlight enables vitamin D production, needed for bone health, immunity, muscles and more. Light exposure controls our sleep-wake cycles, too, activating brain chemicals and hormonal responses in daylight, and winding down bodily functions for sleep as it fades into night. Daylight-simulating devices are a common remedy for people with seasonal affective disorder (Sad) to combat seasonal emotional slumps. So there’s no doubt we need light energy to function well.

Types of Light Therapy

While Sad lamps tend to use a mixture of light frequencies from the blue end of the spectrum, consumer light therapy products mostly feature red and infrared emissions. In rigorous scientific studies, such as Chazot’s investigations into the effects of infrared on brain cells, finding the right frequency is key. Photons represent electromagnetic waves, spanning from low-energy radio waves to short-wavelength gamma rays. Light-based treatment employs mid-spectrum wavelengths, the highest energy of those being invisible ultraviolet, then visible light (all the colours we see in a rainbow) and infrared light visible through night vision technology.

UV light has been used by medical dermatologists for many years to treat chronic skin conditions such as eczema, psoriasis and vitiligo. It affects cellular immune responses, “and suppresses swelling,” says Dr Bernard Ho. “There’s lots of evidence for phototherapy.” UVA reaches deeper skin layers compared to UVB, while the LEDs in consumer devices (typically emitting red, infrared or blue wavelengths) “typically have shallower penetration.”

Risk Assessment and Professional Supervision

Potential UVB consequences, like erythema or pigmentation, are well known but in medical devices the light is delivered in a “narrow-band” form – signifying focused frequency bands – which minimises the risks. “Treatment is monitored by medical staff, so the dosage is monitored,” notes the specialist. Essentially, the lightbulbs are calibrated by medical technicians, “to ensure that the wavelength that’s being delivered is fit for purpose – different from beauty salons, where it’s a bit unregulated, and we don’t really know what wavelengths are being used.”

Commercial Products and Research Limitations

Colored light diodes, he says, “aren’t really used in the medical sense, though they might benefit some issues.” Red LEDs, it is proposed, help boost blood circulation, oxygen uptake and cell renewal in the skin, and stimulate collagen production – a primary objective in youth preservation. “Research exists,” says Ho. “Although it’s not strong.” Nevertheless, amid the sea of devices now available, “we’re uncertain whether commercial devices replicate research conditions. Optimal treatment times are unknown, proper positioning requirements, if benefits outweigh potential risks. Many uncertainties remain.”

Treatment Areas and Specialist Views

Initial blue-light devices addressed acne bacteria, microorganisms connected to breakouts. Research support isn’t sufficient for standard medical recommendation – even though, notes the dermatologist, “it’s often seen in medical spas or aesthetics practices.” Individuals include it in their skincare practices, he says, but if they’re buying a device for home use, “we advise cautious experimentation and safety verification. If it’s not medically certified, standards are somewhat unclear.”

Cutting-Edge Studies and Biological Processes

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 says. The numerous reported benefits have generated doubt regarding phototherapy – that results appear unrealistic. However, scientific investigation has altered his perspective.

Chazot mostly works on developing drug treatments for neurodegenerative diseases, however two decades past, a doctor developing photonic antiviral treatment consulted his scientific background. “He designed tools for biological testing,” he explains. “I was quite suspicious. The specific wavelength measured approximately 1070nm, that many assumed was biologically inert.”

What it did have going for it, though, was that it travelled through water easily, enabling deeper tissue penetration.

Mitochondrial Impact and Cognitive Support

Additional research indicated infrared affected cellular mitochondria. These organelles generate cellular energy, creating power for cellular operations. “All human cells contain mitochondria, even within brain tissue,” explains the neuroscientist, who concentrated on cerebral applications. “Studies demonstrate enhanced cerebral circulation with light treatment, which is always very good.”

With 1070 treatment, cellular power plants create limited oxidative molecules. At controlled levels these compounds, explains the expert, “activates protective proteins that safeguard mitochondria, preserve cell function and eliminate damaged proteins.”

Such mechanisms indicate hope for cognitive disorders: antioxidant, anti-inflammatory, and waste removal – autophagy representing cellular waste disposal.

Current Research Status and Professional Opinions

The last time Chazot checked the literature on using the 1070 wavelength on human dementia patients, he says, approximately 400 participants enrolled in multiple trials, comprising his early research projects