🔗 Share this article

Light-based treatment is clearly enjoying a surge in popularity. There are now available light-emitting tools designed to address complexion problems and aging signs along with sore muscles and gum disease, the newest innovation is an oral care tool enhanced with miniature red light sources, promoted by the creators as “a significant discovery in at-home oral care.” Globally, the industry reached $1 billion in 2024 and is forecast to expand to $1.8 billion by 2035. Options include full-body infrared sauna sessions, which use infrared light to warm the body directly, the thermal energy targets your tissues immediately. As claimed by enthusiasts, it feels similar to a full-body light therapy session, enhancing collagen production, soothing sore muscles, alleviating inflammatory responses and long-term ailments and potentially guarding against cognitive decline.

The Science and Skepticism

“It feels almost magical,” says Paul Chazot, professor in neuroscience at Durham University and a convert to the value of light therapy. Naturally, we know light influences biological functions. Our bodies produce vitamin D through sun exposure, needed for bone health, immunity, muscles and more. Sunlight regulates our circadian rhythms, too, stimulating neurotransmitter and hormone production during daytime, and winding down bodily functions for sleep as it fades into night. Sunlight-imitating lamps frequently help individuals with seasonal depression to combat seasonal emotional slumps. So there’s no doubt we need light energy to function well.

Types of Light Therapy

Although mood lamps generally utilize blue-spectrum frequencies, 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. Light constitutes electromagnetic energy, spanning from low-energy radio waves to high-energy gamma radiation. Light-based treatment uses wavelengths around the middle of this spectrum, the highest energy of those being invisible ultraviolet, then the visible spectrum we perceive as colors and infrared light visible through night vision technology.

Dermatologists have utilized UV therapy for extensive periods for addressing long-term dermatological issues like vitiligo. It works on the immune system within cells, “and reduces inflammatory processes,” says a dermatology expert. “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) “generally affect surface layers.”

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 decreases danger. “It’s supervised by a healthcare professional, thus exposure is controlled,” notes the specialist. Essentially, the lightbulbs are calibrated by medical technicians, “to ensure that the wavelength that’s being delivered is fit for purpose – unlike in tanning salons, where oversight might be limited, and wavelength accuracy isn’t verified.”

Commercial Products and Research Limitations

Red and blue LEDs, he explains, “aren’t typically employed clinically, though they might benefit some issues.” Red LEDs, it is proposed, improve circulatory function, oxygen uptake and skin cell regeneration, and promote collagen synthesis – an important goal for anti-aging. “Studies are available,” comments the expert. “But it’s not conclusive.” Regardless, with numerous products on the market, “we’re uncertain whether commercial devices replicate research conditions. We don’t know the duration, how close the lights should be to the skin, whether or not that will increase the risk versus the benefit. Numerous concerns persist.”

Targeted Uses and Expert Opinions

One of the earliest blue-light products targeted Cutibacterium acnes, bacteria linked to pimples. Research support isn’t sufficient for standard medical recommendation – despite the fact that, says Ho, “it’s often seen in medical spas or aesthetics practices.” Certain patients incorporate it into their regimen, he says, but if they’re buying a device for home use, “we just tell them to try it carefully and to make sure it has been assessed for safety. Without proper medical classification, standards are somewhat unclear.”

Advanced Research and Cellular Mechanisms

At the same time, in a far-flung field of pioneering medical science, 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 says. Multiple claimed advantages have created skepticism toward light treatment – that it’s too good to be true. However, scientific investigation has altered his perspective.

Chazot mostly works on developing drug treatments for neurodegenerative diseases, but over 20 years ago, a physician creating light-based cold sore therapy requested his biological knowledge. “He developed equipment for cellular and insect experiments,” he says. “I was pretty sceptical. This particular frequency was around 1070 nanometers, that nobody believed did anything biological.”

The advantage it possessed, however, was that it travelled through water easily, 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 are the powerhouses of cells, producing fuel for biological processes. “All human cells contain mitochondria, including the brain,” explains the neuroscientist, who, as a neuroscientist, decided to focus the research on brain cells. “It has been shown that in humans this light therapy increases blood flow into the brain, which is generally advantageous.”

Using 1070nm wavelength, energy organelles generate minimal reactive oxygen compounds. In limited quantities these molecules, 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: oxidative protection, anti-inflammatory, 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 reports, about 400 people were taking part in four studies, incorporating his preliminary American studies