‘It seems like sorcery’: is light therapy truly capable of improving your skin, whitening your teeth, and strengthening your joints?

Light-based treatment is clearly enjoying a wave of attention. You can now buy illuminated devices designed to address skin conditions and wrinkles to aching tissues and gum disease, the latest being a toothbrush outfitted with small red light diodes, marketed by the company as “a significant discovery for domestic dental hygiene.” Globally, the sector valued at $1bn last year is expected to increase to $1.8bn within the next decade. You can even go and sit in an infrared sauna, that employ light waves rather than traditional heat sources, the thermal energy targets your tissues immediately. According to its devotees, the experience resembles using an LED facial mask, stimulating skin elasticity, soothing sore muscles, alleviating inflammatory responses and long-term ailments while protecting against dementia.

The Science and Skepticism

“It feels almost magical,” notes a neuroscience expert, who has researched light therapy for two decades. Certainly, we know light influences biological functions. Our bodies produce vitamin D through sun exposure, crucial for strong bones, immune defense, and tissue repair. Natural light synchronizes our biological clocks, as well, activating brain chemicals and hormonal responses in daylight, and signaling the body to slow down for nighttime. Daylight-simulating devices frequently help individuals with seasonal depression to elevate spirits during colder months. So there’s no doubt we need light energy to function well.

Different Light Modalities

Whereas seasonal affective disorder devices typically employ blue-range light, the majority of phototherapy tools use red or near-infrared wavelengths. In serious clinical research, such as Chazot’s investigations into the effects of infrared on brain cells, determining the precise frequency is essential. Light constitutes electromagnetic energy, extending from long-wavelength radiation to high-energy gamma radiation. Phototherapy, or light therapy uses wavelengths around the middle of this spectrum, including invisible ultraviolet radiation, then visible light (all the colours we see in a rainbow) and infrared light visible through night vision technology.

Ultraviolet treatment has been employed by skin specialists for decades to manage persistent skin disorders including eczema and psoriasis. It modulates intracellular immune mechanisms, “and suppresses swelling,” explains Dr Bernard Ho. “Considerable data validates phototherapy.” UVA goes deeper into the skin than UVB, while the LEDs in consumer devices (typically emitting red, infrared or blue wavelengths) “generally affect surface layers.”

Safety Protocols and Medical Guidance

UVB radiation effects, like erythema or pigmentation, are recognized but medical equipment uses controlled narrow-band delivery – indicating limited wavelength spectrum – that reduces potential hazards. “Treatment is monitored by medical staff, thus exposure is controlled,” explains the dermatologist. Essentially, the light sources are adjusted by technical experts, “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 light sources, he explains, “don’t have strong medical applications, but could assist with specific concerns.” Red LEDs, it is proposed, help boost blood circulation, oxygen absorption and dermal rejuvenation, and activate collagen formation – a key aspiration in anti-ageing effects. “The evidence is there,” states the dermatologist. “But it’s not conclusive.” 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, whether or not that will increase the risk versus the benefit. Many uncertainties remain.”

Targeted Uses and Expert Opinions

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 – although, says Ho, “it’s often seen in medical spas or aesthetics practices.” Some of his patients use it as part of their routine, he mentions, 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. Unless it’s a medical device, standards are somewhat unclear.”

Cutting-Edge Studies and Biological Processes

Simultaneously, 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 results appear unrealistic. However, scientific investigation has altered his perspective.

The scientist mainly develops medications for neurological conditions, but over 20 years ago, a physician creating light-based cold sore therapy requested his biological knowledge. “He designed tools for biological testing,” he says. “I was quite suspicious. The specific wavelength measured approximately 1070nm, which most thought had no biological effect.”

The advantage it possessed, however, was its efficient water penetration, enabling deeper tissue penetration.

Cellular Energy and Neurological Benefits

Growing data suggested infrared influenced energy-producing organelles. Mitochondria are the powerhouses of cells, creating power for cellular operations. “Mitochondria exist throughout the body, even within brain tissue,” notes the researcher, who prioritized neurological investigations. “Research confirms improved brain blood flow with phototherapy, which is always very good.”

Using 1070nm wavelength, cellular power plants create limited oxidative molecules. In limited quantities these molecules, says Chazot, “activates protective proteins that safeguard mitochondria, preserve cell function and eliminate damaged proteins.”

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

Ongoing Study Progress and Specialist Evaluations

When recently reviewing 1070nm research for cognitive decline, he says, about 400 people were taking part in four studies, including his own initial clinical trials in the US