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

Light therapy is certainly having a surge in popularity. You can now buy illuminated devices targeting issues like skin conditions and wrinkles as well as muscle pain and gum disease, recently introduced is a toothbrush enhanced with tiny red LEDs, promoted by the creators as “a significant discovery in personal mouth health.” Worldwide, 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, stimulating skin elasticity, soothing sore muscles, reducing swelling and chronic health conditions while protecting against dementia.

Understanding the Evidence

“It feels almost magical,” notes a Durham University professor, who has researched light therapy for two decades. Of course, certain impacts of light on human physiology are proven. Sunlight helps us make vitamin D, crucial for strong bones, immune defense, and tissue repair. Natural light synchronizes our biological clocks, additionally, activating brain chemicals and hormonal responses in daylight, and signaling the body to slow down for nighttime. Artificial sun lamps are standard treatment for winter mood disorders to boost low mood in winter. So there’s no doubt we need light energy to function well.

Types of Light Therapy

Although mood lamps generally utilize blue-spectrum frequencies, 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, identifying the optimal wavelength is crucial. Photons represent electromagnetic waves, extending from long-wavelength radiation to high-energy gamma radiation. Light-based treatment employs mid-spectrum wavelengths, including invisible ultraviolet radiation, followed by visible light encompassing rainbow colors and finally infrared detectable with special equipment.

UV light has been used by medical dermatologists for many years for addressing long-term dermatological issues like vitiligo. It works on the immune system within cells, “and dampens down inflammation,” explains a skin specialist. “Considerable data validates phototherapy.” UVA penetrates skin more deeply than UVB, while the LEDs in consumer devices (which generally deliver red, infrared or blue light) “generally affect surface layers.”

Safety Protocols and Medical Guidance

UVB radiation effects, such as burning or tanning, are understood but clinical devices employ restricted wavelength ranges – indicating limited wavelength spectrum – which decreases danger. “Treatment is monitored by medical staff, thus exposure is controlled,” notes the specialist. Most importantly, the lightbulbs are calibrated by medical technicians, “to guarantee appropriate wavelength emission – different from beauty salons, where oversight might be limited, and emission spectra aren’t confirmed.”

Consumer Devices and Evidence Gaps

Red and blue LEDs, he says, “aren’t typically employed clinically, but they may help with certain conditions.” Red light devices, some suggest, help boost blood circulation, oxygen absorption and cell renewal in the skin, and stimulate collagen production – a key aspiration in anti-ageing effects. “The evidence is there,” states the dermatologist. “But it’s not conclusive.” In any case, with numerous products on the market, “we don’t know whether or not the lights emitted are reflective of the research that has been done. Appropriate exposure periods aren’t established, ideal distance from skin surface, whether or not that will increase the risk versus the benefit. There are lots of questions.”

Targeted Uses and Expert Opinions

Early blue-light applications focused on skin microbes, a microbe associated with acne. Research support isn’t sufficient for standard medical recommendation – despite the fact that, notes the dermatologist, “it’s often seen in medical spas or aesthetics practices.” Some of his patients use it as part of their routine, 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. If it’s not medically certified, the regulation is a bit grey.”

Cutting-Edge Studies and Biological Processes

At the same time, 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 says. The numerous reported benefits have generated doubt regarding phototherapy – that claims seem exaggerated. Yet, experimental evidence has transformed his viewpoint.

Chazot mostly works on developing drug treatments for neurodegenerative diseases, however two decades past, a GP who was developing an antiviral light treatment for cold sores sought his expertise as a biologist. “He developed equipment for cellular and insect experiments,” he explains. “I remained doubtful. This particular frequency was around 1070 nanometers, that nobody believed did anything biological.”

What it did have going for it, however, was that it travelled through water easily, enabling deeper tissue penetration.

Mitochondrial Effects and Brain Health

More evidence was emerging at the time that infrared light targeted the mitochondria in cells. These organelles generate cellular energy, creating power for cellular operations. “Mitochondria exist throughout the body, particularly in neural cells,” notes the researcher, who prioritized neurological investigations. “Research confirms improved brain blood flow with phototherapy, which is consistently beneficial.”

Using 1070nm wavelength, energy organelles generate minimal reactive oxygen compounds. In low doses this substance, explains the expert, “triggers guardian proteins that maintain organelle health, preserve cell function and eliminate damaged 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.

Current Research Status and Professional Opinions

Upon examining current studies on light therapy for dementia, he reports, approximately 400 participants enrolled in multiple trials, comprising his early research projects