‘It appears magical’: does light therapy actually deliver clearer skin, healthier teeth, and more resilient joints?

Light therapy is clearly enjoying a surge in popularity. Consumers can purchase illuminated devices for everything from skin conditions and wrinkles along with muscle pain and gum disease, the latest being a dental hygiene device equipped with tiny red LEDs, promoted by the creators as “a significant discovery for domestic dental hygiene.” Internationally, the market was worth $1bn in 2024 and is projected to grow to $1.8bn by 2035. There are even infrared saunas available, that employ light waves rather than traditional heat sources, your body is warmed directly by infrared light. According to its devotees, it’s like bathing in one of those LED-lit beauty masks, enhancing collagen production, relaxing muscles, relieving inflammation and long-term ailments as well as supporting brain health.

The Science and Skepticism

“It appears somewhat mystical,” says a neuroscience expert, professor in neuroscience at Durham University and a convert to the value of light therapy. Naturally, certain impacts of light on human physiology are proven. Sunlight enables vitamin D production, essential for skeletal strength, immune function, and muscular health. Light exposure controls our sleep-wake cycles, too, activating brain chemicals and hormonal responses in daylight, 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.

Various Phototherapy Approaches

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, like examinations of infrared influence on cerebral tissue, identifying the optimal wavelength is crucial. Light is a form of electromagnetic radiation, extending from long-wavelength radiation to high-energy gamma radiation. Light-based treatment employs mid-spectrum wavelengths, with ultraviolet representing the higher energy invisible light, followed by visible light encompassing rainbow colors and then infrared (which we can see with night-vision goggles).

Ultraviolet treatment has been employed by skin specialists for decades for addressing long-term dermatological issues like vitiligo. It affects cellular immune responses, “and reduces inflammatory processes,” says Dr Bernard Ho. “Considerable data validates phototherapy.” UVA goes deeper into the skin than UVB, while the LEDs in consumer devices (which generally deliver red, infrared or blue light) “tend to be a bit more superficial.”

Safety Considerations and Medical Oversight

Potential UVB consequences, like erythema or pigmentation, are understood but clinical devices employ restricted wavelength ranges – meaning smaller wavelengths – which minimises the risks. “Therapy is overseen by qualified practitioners, meaning intensity is regulated,” notes the specialist. And crucially, the devices are tuned by qualified personnel, “to confirm suitable light frequency output – unlike in tanning salons, where oversight might be limited, and emission spectra aren’t confirmed.”

Home Devices and Scientific Uncertainty

Red and blue LEDs, he notes, “don’t have strong medical applications, but they may help with certain conditions.” Red wavelength therapy, proponents claim, help boost blood circulation, oxygen absorption and skin cell regeneration, and stimulate collagen production – a key aspiration in anti-ageing effects. “Research exists,” states the dermatologist. “Although it’s not strong.” Regardless, given the plethora of available tools, “we’re uncertain whether commercial devices replicate research conditions. We don’t know the duration, proper positioning requirements, if benefits outweigh potential risks. Many uncertainties remain.”

Specific Applications and Professional Perspectives

Early blue-light applications focused on skin microbes, microorganisms connected to breakouts. The evidence for its efficacy isn’t strong enough for it to be routinely prescribed by doctors – even though, explains the specialist, “it’s often seen in medical spas or aesthetics practices.” Some of his patients use it as part of their routine, he says, however for consumer products, “we recommend careful testing and security confirmation. Unless it’s a medical device, standards are somewhat unclear.”

Innovative Investigations and Molecular Effects

Meanwhile, in innovative scientific domains, Chazot has been experimenting with brain cells, revealing various pathways for light-enhanced cell function. “Virtually all experiments with specific wavelengths showed beneficial and safeguarding effects,” he reports. It is partly these many and varied positive effects on cellular health that have driven skepticism about light therapy – that results appear unrealistic. Yet, experimental evidence has transformed his viewpoint.

The researcher primarily focuses on pharmaceutical solutions for brain disorders, but over 20 years ago, a doctor developing photonic antiviral treatment consulted his scientific background. “He developed equipment for cellular and insect experiments,” he explains. “I was quite suspicious. This particular frequency was around 1070 nanometers, which most thought had no biological effect.”

Its beneficial characteristic, however, was that it travelled through water easily, meaning it could penetrate the body more deeply.

Mitochondrial Impact and Cognitive Support

Additional research indicated infrared affected cellular mitochondria. These organelles generate cellular energy, producing fuel for biological processes. “Every cell in your body has mitochondria, including the brain,” explains the neuroscientist, who, as a neuroscientist, decided to focus the research on brain cells. “Studies demonstrate enhanced cerebral circulation with light treatment, which is always very good.”

With 1070 treatment, cellular power plants create limited oxidative molecules. In limited quantities these molecules, explains the expert, “stimulates so-called chaperone proteins which look after your mitochondria, look after your cells and also deal with the unwanted proteins.”

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

Ongoing Study Progress and Specialist Evaluations

The last time Chazot checked the literature on using the 1070 wavelength on human dementia patients, he reports, about 400 people were taking part in four studies, including his own initial clinical trials in the US