PBM/LLLT in mainstream medicine

By Jan Tunér

The acceptance of PBM is progressing but at a slow rate. This is partly due to lack of knowledge about the optimal parameters and quality problems in the PBM literature. Still, things are moving forward. In 1995 Basford (1) published an article with the title Low intensity laser therapy: still not an established clinical tool. There were good reasons for the title, very few scientific investigations available and much knowledge was based upon anecdotal reports. But things changed and in 2010 the same author (2) participated in a study in PBM for tendinopathy. In the conclusion, the authors state: LLLT can potentially be effective in treating tendinopathy when recommended dosages are used. The 12 positive studies provide strong evidence that positive outcomes are associated with the use of current dosage recommendations for the treatment of tendinopathy.

This proves that Max Planck was not entirely right when he coined the sentences: An important scientific innovation rarely makes its way by gradually winning over and converting its opponents: it rarely happens that Saul becomes Paul. What does happen is that its opponents gradually die out and that the growing generation is familiarized with the idea from the beginning.

But how come PBM was met with such scepticism and even hostility? After all, a research group from Boston (3-7) stumbled upon some of the basic effects of PBM already in 1964. And published in prestigious scientific journals. My belief is that nobody, not even the authors, realized what they had found. Later on, the Mester group in Budapest (8-10) continued on the work of McGuff. However, their studies were published in Hungarian and German and very few researchers in “the West” read them. Most of the basic principles of PBM were established by the Mester group, but remained vastly unknown. In the beginning of the 80s, PBM was commercialised in Europe and in North America. Marketing was centred upon a few positive studies (11-13), using a 0.9 mW HeNe laser of 632.8 nm. These studies were met with scepticism and control studies could not confirm the effects, although they were on the right trail. From that moment, leading healthcare decision makers had made up their minds about this strange treatment.

Indeed, a growing number of investigations were gradually published, supporting the efficacy of the treatment. However, research quality was often low and even the proponents of PBM were worried about the randomly chosen, and incompletely recorded laser parameters. A common conclusion in systematic reviews was that there was some evidence for PBM in the chosen area, but the reported parameter were so different and no final conclusions could be made. This is up till today a problem (13).

But further to that, fraud research papers were presented, like those of Tomas Lundeberg, featured in LaserAnnals 4/2016 (link). Coming from a prestigious university, they were accepted as the gospel truth and caused a lot of harm. The situation was not favoured by aggressive marketing of very low powered and expensive lasers. Further to that, some manufacturers were selling cheap and low powered LEDs and claiming them to be lasers. And if honest about being LEDs, the scientific claims behind them were taken from the laser literature.

Looking back, PBM has had a rough road trying to enter mainstream medicine. Today, it has at least a foot in the door. Research quality and quantity has improved, more is known about the mechanisms and like Planck proposed, many opponents have died or retired. And upon that, the serious side effects of pharmaceuticals are coming in focus, while the cost for health care is skyrocketing (14). PBM offers a solution to several of these concerns. The growing generation will know.




  1. Basford JR. Low intensity laser therapy: still not an established clinical tool. Lasers Surg Med. 1995;16(4):331-42.
  2. Tumilty S, Munn J, McDonough S, Hurley DA, Basford JR, Baxter GD. Low level laser treatment of tendinopathy: a systematic review with meta-analysis. Photomed Laser Surg. 2010 Feb;28(1):3-16.
  3. McGuff P E, Bell E J. The effect of laser energy radiation on bacteria. Med Biol Illus. 1966; 16 (3): 191-193.
  4. McGuff P E, Gottlieb L S, Katayama I, Levy C K. Comparative study of effects of laser and/or ionizing radiation therapy on experimental or human malignant tumors. Am J Roentgenol Radium Ther Nucl Med. 1966; 96 (3): 744-748.
  5. McGuff P E, Deterling R A Jr, Gottlieb L S. Laser radiation for metastatic malignant melanoma. JAMA. 1966; 31; 195 (5): 393-394.
  6. McGuff P E. Laser radiation for basal cell carcinoma. Dermatologica. 1966; 133 (5): 379-383.
  7. McGuff P E. Tumoricidal effect of laser radiation on malignant tumors. Int Ophthalmol Clin. 1966; 6 (2): 379-386.
  8. Mester E et al. Auswirkungen direkter Laserbestrahlung auf menschliche Lymphozyten. [Effects of direct laser radiation on human lymphocytes]. Arch Dermatol Res. 1978; 263 (3): 241-245.
  9. Mester E. et al. Untersuchungen über die hemmende bzw. fördernde Wirkung der Laserstrahlen. [Studies on the inhibiting and activating effects of laser beams]. Langenbecks Arch Klin Chir. 1968; 322: 1022-1027.
  10. Bihari I, Mester A. The biostimulative effect of low level laser therapy of long-standing crural ulcer using Helium Neon laser, Helium Neon plus infrared lasers and noncoherent light: Preliminary report of a randomized double blind comparative study. Laser Therapy. 1989; 1 (2): 97-102.
  11. Walker J et al. Relief from Chronic Pain by Low Power Laser Irradiation. Neuroscience Letters. 1983; 43: 339-344.
  12. Walker J et al. Laser Therapy for pain of Rheumatoid Arthritis. The Clinical Journal of Pain. 1987; 3 (53): 54-59.
  13. Tunér J, Jenkins PA. Parameter Reproducibility in Photobiomodulation. Photomed Laser Surg. 2016; 34 (3): 91-9.
  14. Peter C Gotzsche. Deadly medicine and organised crime: How Big Pharma Has Corrupted Healthcare. Radcliffe. 2013.