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

Light-based treatment is definitely experiencing a moment. You can now buy light-emitting tools for everything from dermatological concerns and fine lines along with muscle pain and gum disease, the latest being a toothbrush outfitted with small red light diodes, marketed by the company as “a breakthrough in at-home oral care.” Internationally, the market was worth $1bn in 2024 and is projected to grow to $1.8bn by 2035. Options include full-body infrared sauna sessions, where instead of hot coals (real or electric) heating the air, your body is warmed directly by infrared light. As claimed by enthusiasts, it’s like bathing in one of those LED-lit beauty masks, boosting skin collagen, easing muscle tension, reducing swelling and chronic health conditions and potentially guarding against cognitive decline.

Research and Reservations

“It feels almost magical,” says Paul Chazot, who has researched light therapy for two decades. Of course, 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, stimulating neurotransmitter and hormone production during daytime, and winding down bodily functions for sleep as it fades into night. Sunlight-imitating lamps are standard treatment for winter mood disorders to boost low mood in winter. Clearly, light energy is essential for optimal functioning.

Various Phototherapy Approaches

While Sad lamps tend to use a mixture of light frequencies from the blue end of the spectrum, most other light therapy devices deploy red or infrared light. During advanced medical investigations, such as Chazot’s investigations into the effects of infrared on brain cells, determining the precise frequency is essential. Photons represent electromagnetic waves, extending from long-wavelength radiation to high-energy gamma radiation. Phototherapy, or light therapy utilizes intermediate light frequencies, the highest energy of those being invisible ultraviolet, then the visible spectrum we perceive as colors and infrared light visible through night vision technology.

Ultraviolet treatment has been employed by skin specialists for decades to treat chronic skin conditions such as eczema, psoriasis and vitiligo. It modulates intracellular immune mechanisms, “and dampens down inflammation,” notes a dermatology expert. “Substantial research supports light therapy.” 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

UVB radiation effects, like erythema or pigmentation, are recognized but medical equipment uses controlled narrow-band delivery – signifying focused frequency bands – which decreases danger. “It’s supervised by a healthcare professional, thus exposure is controlled,” explains the dermatologist. Essentially, the devices are tuned by qualified personnel, “to ensure that the wavelength that’s being delivered is fit for purpose – different from beauty 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 light sources, he explains, “aren’t really used in the medical sense, but could assist with specific concerns.” Red light devices, some suggest, improve circulatory function, oxygen absorption and dermal rejuvenation, and promote collagen synthesis – a key aspiration in anti-ageing effects. “Research exists,” comments the expert. “Although it’s not strong.” In any case, given the plethora of available tools, “it’s unclear if device outputs match study parameters. We don’t know the duration, ideal distance from skin surface, if benefits outweigh potential risks. There are lots of questions.”

Specific Applications and Professional Perspectives

Initial blue-light devices addressed acne bacteria, bacteria linked to pimples. Research support isn’t sufficient for standard medical recommendation – even though, notes the dermatologist, “it’s frequently employed in beauty centers.” Individuals include it in their skincare practices, 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. Without proper medical classification, standards are somewhat unclear.”

Innovative Investigations and Molecular Effects

At the same time, in advanced research areas, 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 reports. Multiple claimed advantages have created skepticism toward light treatment – that claims seem exaggerated. Yet, experimental evidence has transformed his viewpoint.

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 developed equipment for cellular and insect experiments,” he recalls. “I was quite suspicious. It was an unusual wavelength of about 1070 nanometres, which most thought had no biological effect.”

Its beneficial characteristic, however, was its ability to transmit through aqueous environments, enabling deeper tissue penetration.

Cellular Energy and Neurological Benefits

More evidence was emerging at the time that infrared light targeted the mitochondria in cells. These organelles generate cellular energy, producing fuel for biological processes. “Every cell in your body has mitochondria, including the brain,” notes the researcher, who concentrated on cerebral applications. “It has been shown that in humans this light therapy increases blood flow into the brain, which is consistently beneficial.”

With specific frequency application, mitochondria also produce a small amount of a molecule known as reactive oxygen species. In low doses this substance, says Chazot, “stimulates so-called chaperone proteins which look after your mitochondria, look after your cells and also deal with the unwanted proteins.”

Such mechanisms indicate hope for cognitive disorders: oxidative protection, swelling control, and cellular cleanup – autophagy being the process the cell uses to clear unwanted damaging proteins.

Ongoing Study Progress and Specialist Evaluations

The last time Chazot checked the literature on using the 1070 wavelength on human dementia patients, he states, several hundred individuals participated in various investigations, comprising his early research projects