🔗 Share this article

Light-based treatment is certainly having a moment. There are now available glowing gadgets targeting issues like dermatological concerns and fine lines along with muscle pain and periodontal issues, recently introduced is a dental hygiene device equipped with tiny red LEDs, marketed by the company as “a breakthrough in personal mouth health.” Worldwide, 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, your body is warmed directly by infrared light. Based on supporter testimonials, the experience resembles using an LED facial mask, boosting skin collagen, relaxing muscles, alleviating inflammatory responses and chronic health conditions and potentially guarding against cognitive decline.

The Science and Skepticism

“It feels almost magical,” says a neuroscience expert, a scientist who has studied phototherapy extensively. Certainly, some of light’s effects on our bodies are well established. Our bodies produce vitamin D through sun exposure, needed for bone health, immunity, muscles and more. Light exposure controls our sleep-wake cycles, as well, activating brain chemicals and hormonal responses in daylight, and winding down bodily functions for sleep as it fades into night. Sunlight-imitating lamps frequently help individuals with seasonal depression to boost low mood in winter. Clearly, light energy is essential for optimal functioning.

Types of Light Therapy

Although mood lamps generally utilize blue-spectrum frequencies, consumer light therapy products mostly feature red and infrared emissions. During advanced medical investigations, such as Chazot’s investigations into the effects of infrared on brain cells, identifying the optimal wavelength is crucial. Light constitutes electromagnetic energy, spanning from low-energy radio waves to short-wavelength gamma rays. Light-based treatment employs mid-spectrum wavelengths, including invisible ultraviolet radiation, 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 manage persistent skin disorders including eczema and psoriasis. It works on the immune system within cells, “and reduces inflammatory processes,” explains Dr Bernard Ho. “Substantial research supports light therapy.” UVA reaches deeper skin layers compared to UVB, while the LEDs in consumer devices (which generally deliver red, infrared or blue light) “typically have shallower penetration.”

Safety Considerations and Medical Oversight

UVB radiation effects, including sunburn or skin darkening, are well known but in medical devices the light is delivered in a “narrow-band” form – indicating limited wavelength spectrum – that reduces potential hazards. “Treatment is monitored by medical staff, meaning intensity is regulated,” notes the specialist. Most importantly, the light sources are adjusted by technical experts, “to guarantee appropriate wavelength emission – unlike in tanning salons, where it’s a bit unregulated, and emission spectra aren’t confirmed.”

Commercial Products and Research Limitations

Colored light diodes, he explains, “aren’t typically employed clinically, though they might benefit some issues.” Red light devices, some suggest, enhance blood flow, oxygen utilization and cell renewal in the skin, and activate collagen formation – a primary objective in youth preservation. “Studies are available,” states the dermatologist. “However, it’s limited.” In any case, with numerous products on the market, “we’re uncertain whether commercial devices replicate research conditions. Optimal treatment times are unknown, ideal distance from skin surface, if benefits outweigh potential risks. Many uncertainties remain.”

Specific Applications and Professional Perspectives

Early blue-light applications focused on skin microbes, a microbe associated with acne. The evidence for its efficacy isn’t strong enough for it to be routinely prescribed by doctors – despite the fact that, explains the specialist, “it’s commonly used in cosmetic clinics.” Certain patients incorporate it into their regimen, he observes, however for consumer products, “we just tell them to try it carefully and to make sure it has been assessed for safety. Unless it’s a medical device, the regulation is a bit grey.”

Innovative Investigations and Molecular Effects

Simultaneously, in innovative scientific domains, scientists have been studying cerebral tissue, revealing various pathways for light-enhanced cell function. “Pretty much everything I did with the light at that particular wavelength was positive and protective,” he reports. Multiple claimed advantages have created skepticism toward light treatment – that claims seem exaggerated. Yet, experimental evidence has transformed his viewpoint.

The researcher primarily focuses on pharmaceutical solutions for brain disorders, however two decades past, a doctor developing photonic antiviral treatment consulted his scientific background. “He created some devices so that we could work with them with cells and with fruit flies,” he recalls. “I was quite suspicious. This particular frequency was around 1070 nanometers, that nobody believed did anything biological.”

What it did have going for it, however, was its efficient water penetration, allowing substantial bodily penetration.

Mitochondrial Effects and Brain Health

More evidence was emerging at the time that infrared light targeted the mitochondria in cells. Mitochondria are the powerhouses of cells, creating power for cellular operations. “Mitochondria exist throughout the body, particularly in neural cells,” says Chazot, 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 specific frequency application, energy organelles generate minimal reactive oxygen compounds. In low doses this substance, notes the scientist, “activates protective proteins that safeguard mitochondria, protect cellular integrity and manage defective proteins.”

All of these mechanisms appear promising for treating a brain disease: free radical neutralization, swelling control, and pro-autophagy – autophagy being the process the cell uses to clear unwanted damaging proteins.

Ongoing Study Progress and Specialist Evaluations

Upon examining current studies on light therapy for dementia, he says, approximately 400 participants enrolled in multiple trials, incorporating his preliminary American studies