Shedding Light on Red Light Therapy: Unveiling Its Hidden History

Shedding Light on Red Light Therapy: Unveiling Its Hidden History


Red Light Therapy (RLT),[ or known as  Photbiomodulation PBM, Low Level Laser Light Therapy (LLLT)] is recognized today as a transformative tool in healing and wellness. While often linked to modern scientific advancements, particularly NASA's research, its history dates back much further. This blog delves into the true origins of Red Light Therapy, tracing its journey from the 19th century to its current prominence.

Niels Finsen: The Pioneer of Light Therapy

The story of Red Light Therapy begins in the late 19th century with Niels Finsen, a Faroese-Danish physician and scientist.

- Niels Finsen's Groundbreaking Work: Finsen is celebrated for his pioneering work in the treatment of skin diseases, particularly lupus vulgaris, using concentrated light radiation.
- 1893 Breakthrough: His significant breakthrough in 1893 involved using light to treat lupus vulgaris, a severe skin infection caused by tuberculosis bacteria. This innovative approach laid the groundwork for phototherapy in modern medicine.
- Nobel Prize Recognition: Finsen's contributions were so impactful that they earned him the Nobel Prize in Physiology or Medicine in 1903, highlighting the therapeutic potential of light.

Endre Mester and the Cold War Barrier

- Endre Mester's Contributions: Fast forward to the 1960s, and we meet Endre Mester in Hungary, who conducted pivotal experiments using low-level laser light for wound healing and hair regrowth.
- The Cold War's Impact: Mester's findings, critical to the advancement of light therapy, were obscured from the Western world due to the Cold War, leading to a delayed recognition and integration into Western medicine.

NASA's Influence: Propagating Light Therapy

- NASA's extensive research in the late 20th century played a significant role in popularizing Red Light Therapy for wound healing in space.
- The misconception that NASA originated RLT stems from the limited exposure to Mester's and earlier work due to geopolitical barriers.

RLT's Historical Context

- The evolution of RLT shares its timeline with other key technological advancements of the 20th century, such as microwaves, soft contact lenses, and cell phones, reflecting a period of rapid scientific progress.

Expansive Research and Modern Applications

- Today, a vast database with over 7,500 publications on Light Therapy exists, underscoring the field's growth and research depth.
- Link to database  for further exploration.
- The U.S. military and elite athletes increasingly use RLT, evidencing its effectiveness in enhancing recovery and performance.

Evolution of Red Light Therapy: From Lasers to LEDs

A pivotal aspect of Red Light Therapy's (RLT) evolution is its shift from laser-based systems to Light Emitting Diodes (LEDs), reflecting broader trends in technological advancement.

  • Early Days with Lasers: Initially, RLT predominantly used laser technology. These low-level lasers (also known as "cold lasers") were effective in delivering concentrated light for therapeutic purposes. However, they were typically more expensive, required operation by trained professionals, and were limited in the area they could treat at any one time.

  • The Emergence of LEDs: Over time, LEDs emerged as a more practical alternative for RLT. They offered several advantages: LEDs were more cost-effective, consumed less power, and were able to cover larger surface areas. This made RLT more accessible and convenient for both clinical and home use.

  • Similarities with TV Technology Evolution: This transition bears resemblance to the evolution of television technology. Televisions evolved from bulky Cathode Ray Tube (CRT) designs to sleeker Plasma and then to LED-based screens. Each of these transitions brought improvements in efficiency, convenience, and performance, though the core function of televisions – displaying images via electronic signals – remained unchanged.

  • Consistent Underlying Science: In RLT, the move from lasers to LEDs did not alter the therapy's fundamental principle – using specific wavelengths of light to stimulate cellular processes for therapeutic benefits. The transition to LEDs simply made the technology more accessible and versatile, similar to how modern TVs have become more user-friendly without changing the basic concept of image display.


Red Light Therapy's journey from Niels Finsen's 19th-century discovery to a modern-day healing tool is a remarkable narrative of scientific endurance and innovation. It showcases how historical advancements, often overlooked, pave the way for contemporary medical practices, continually transforming our approach to health and wellness.