🔗 Share this article

Light-based treatment is clearly enjoying a wave of attention. There are now available light-emitting tools targeting issues like skin conditions and wrinkles to muscle pain and periodontal issues, recently introduced is a toothbrush outfitted with tiny red LEDs, promoted by the creators as “a breakthrough in at-home oral care.” 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, where instead of hot coals (real or electric) heating the air, your body is warmed directly by infrared light. According to its devotees, it feels similar to a full-body light therapy session, boosting skin collagen, soothing sore muscles, reducing swelling and persistent medical issues and potentially guarding against cognitive decline.

Understanding the Evidence

“It feels almost magical,” observes Paul Chazot, a scientist who has studied phototherapy extensively. Of course, certain impacts of light on human physiology are proven. Sunlight enables vitamin D production, crucial for strong bones, immune defense, and tissue repair. Sunlight regulates our circadian rhythms, as well, stimulating neurotransmitter and hormone production during daytime, and winding down bodily functions for sleep as it fades into night. Sunlight-imitating lamps are a common remedy for people with seasonal affective disorder (Sad) to combat seasonal emotional slumps. Clearly, light energy is essential for optimal functioning.

Various Phototherapy Approaches

Although mood lamps generally utilize blue-spectrum frequencies, consumer light therapy products mostly feature red and infrared emissions. During advanced medical investigations, 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 short-wavelength gamma rays. Therapeutic light application uses wavelengths around the middle of this spectrum, 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.

Dermatologists have utilized UV therapy for extensive periods to treat chronic skin conditions such as eczema, psoriasis and vitiligo. It modulates intracellular immune mechanisms, “and reduces inflammatory processes,” notes a skin specialist. “Considerable data validates phototherapy.” UVA goes deeper into the skin than UVB, in contrast to LEDs in commercial products (typically emitting red, infrared or blue wavelengths) “tend to be a bit more superficial.”

Risk Assessment and Professional Supervision

Potential UVB consequences, such as burning or tanning, are well known but in medical devices the light is delivered in a “narrow-band” form – indicating limited wavelength spectrum – which decreases danger. “Treatment is monitored by medical staff, thus exposure is controlled,” says Ho. Essentially, the devices are tuned by qualified personnel, “to confirm suitable light frequency output – unlike in tanning salons, where regulations may be lax, and we don’t really know what wavelengths are being used.”

Home Devices and Scientific Uncertainty

Red and blue LEDs, he says, “aren’t typically employed clinically, but they may help with certain conditions.” Red wavelength therapy, proponents claim, improve circulatory function, oxygen uptake and dermal rejuvenation, and activate collagen formation – a primary objective in youth preservation. “The evidence is there,” says Ho. “However, it’s limited.” In any case, with numerous products on the market, “we’re uncertain whether commercial devices replicate research conditions. Appropriate exposure periods aren’t established, ideal distance from skin surface, the risk-benefit ratio. There are lots of questions.”

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 – although, notes the dermatologist, “it’s frequently employed in beauty centers.” Certain patients incorporate it into their regimen, he says, though when purchasing home devices, “we just tell them to try it carefully and to make sure it has been assessed for safety. Unless it’s a medical device, oversight remains ambiguous.”

Innovative Investigations and Molecular Effects

Meanwhile, in a far-flung field of pioneering medical science, researchers have been testing neural cells, discovering multiple mechanisms for infrared’s cellular benefits. “Pretty much everything I did with the light at that particular wavelength was positive and protective,” he states. Multiple claimed advantages have created skepticism toward light treatment – that results appear unrealistic. But his research has thoroughly changed his mind in that respect.

The scientist mainly develops medications for neurological conditions, however two decades past, a physician creating light-based cold sore therapy requested his biological knowledge. “He created some devices so that we could work with them with cells and with fruit flies,” he says. “I was quite suspicious. The specific wavelength measured approximately 1070nm, which most thought had no biological effect.”

Its beneficial characteristic, though, was its efficient water penetration, enabling deeper tissue 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, producing fuel for biological processes. “All human cells contain mitochondria, even within brain tissue,” notes the researcher, 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 consistently beneficial.”

With 1070 treatment, energy organelles generate minimal reactive oxygen compounds. In low doses this substance, says Chazot, “stimulates so-called chaperone proteins which look after your mitochondria, protect cellular integrity and manage defective proteins.”

Such mechanisms indicate hope for cognitive disorders: free radical neutralization, inflammation reduction, and waste removal – self-digestion mechanisms eliminating harmful elements.

Present Investigation Status and Expert Assessments

The last time Chazot checked the literature on using the 1070 wavelength on human dementia patients, he states, about 400 people were taking part in four studies, comprising his early research projects