What Is Photobiomodulation? Definizione, Storia & Come funziona

PBM didn’t appear out of thin air. Its history stretches back over 120 years and involves Nobel laureates, Cold War-era laboratories, NASA engineers, and a very fortunate accident with mice.

Understanding this history matters because it shows PBM isn’t a wellness fad — it’s a technology with deep scientific roots that took decades to mature.

1903 — Niels Finsen: The First Nobel Prize for Light Therapy

Modern phototherapy began with Danish physician Niels Ryberg Finsen. In 1903, Finsen received the Nobel Prize in Physiology or Medicine for demonstrating that concentrated light could treat lupus vulgaris (skin tuberculosis).

Finsen didn’t discover PBM — his work used different wavelengths. But he established a critical principle that underlies everything that followed: specific wavelengths of light can produce measurable, therapeutic biological effects.

1960 — Theodore Maiman Builds the First Laser

In 1960, physicist Theodore Maiman at Hughes Research Laboratories built the first working laser using a synthetic ruby crystal. For the first time, scientists had a coherent, monochromatic light source — a beam of light at a single, precise wavelength.

This breakthrough made it possible to study exactly how specific wavelengths interact with biological tissue, setting the stage for what came next.

1967 — Endre Mester: The Accidental Discovery That Started It All

This is the pivotal moment.

In 1967, Hungarian physician Endre Mester at Semmelweis University in Budapest was trying to test whether a laser could destroy implanted tumors in mice. He used a low-powered ruby laser (694 nm) — but his laser was far too weak to destroy anything.

The tumors were unaffected. But Mester noticed something unexpected: the shaved skin on the irradiated mice healed faster and their hair grew back more quickly than in the control group.

Rather than dismissing this as a failed experiment, Mester investigated. Over the following years, he conducted studies showing that low-intensity laser light could accelerate wound healing in human patients, stimulate hair regrowth, e ridurre l'infiammazione (Mester et al., 1968).

Mester had discovered what he called “laser biostimulation” — the phenomenon we now call photobiomodulation. His work established three principles that remain central to PBM science today:

1. Low-intensity light can stimulate biological processes — it doesn’t just cut or burn tissue
2. The effect is wavelength-dependent — not any light will do
3. There is an optimal dose — too little does nothing, too much can actually inhibit healing

These principles — especially the third one, conosciuto come il risposta alla dose bifasica — still guide PBM research and device design over half a century later.

1980s–1990s — NASA: From Space Plants to Wound Healing

PBM’s next major chapter came from space research.

In the late 1980s and 1990s, NASA-funded scientists at Marshall Space Flight Center were testing whether LED lights could boost plant growth on long-duration space missions. Red LEDs (670 nm) worked well for plants — but the more significant discovery came when researchers led by Dr. Harry Whelan at the Medical College of Wisconsin found that the same LED wavelengths also accelerated wound healing and cell proliferation in human tissue.

This was transformative for two reasons:

• It proved that LEDs — not just expensive lasers — could produce photobiomodulatory effects
• LEDs were cheaper, safer, and could cover far larger treatment areas

NASA’s research opened the door for the LED-based therapy devices that now dominate both the professional and consumer PBM market.

2000s–2010s — Molecular Mechanisms and Clinical Validation

With LED technology validated, PBM research accelerated:

• 2005: Tiina Karu identifies cytochrome c oxidase as the primary chromophore responsible for PBM — finally providing the molecular mechanism
• 2012: Chung et al. publish “The Nuts and Bolts of Low-Level Laser (Leggero) Therapy”, one of the most comprehensive PBM reviews, cited over 2,000 volte
• 2014: Wunsch & Matuschka publish a controlled clinical trial showing red/NIR LED light significantly reduces wrinkles and increases collagen density
• 2015: “Photobiomodulation therapy” officially adopted as a MeSH term by the U.S. National Library of Medicine
• 2017: Hamblin publishes a major review on PBM’s anti-inflammatory mechanisms
• FDA clearances granted for multiple PBM device categories

2015–Present — The Home Device Revolution

The most recent chapter is the explosion of consumer LED therapy devices. Advances in high-power LED manufacturing, dropping costs, and growing consumer awareness have created a global market worth billions.

Oggi, PBM devices are used in dermatology clinics, physical therapy practices, sports teams, and millions of homes. Manufacturers like WakeLife Beauty now translate decades of PBM research into accessible, quality-controlled LED devices for both professional and consumer use [[2]][doc_2] [[4]][doc_4].