The Lure of Light Therapy

Companies and biohackers are running with the science behind the healing potential of light therapy

Rachel del Valle
Published in
5 min readMay 9, 2019


Credit: robyvannucci/E+/Getty

InIn a recent episode of the Ben Greenfield Fitness: Diet, Fat Loss and Performance podcast, Twitter CEO Jack Dorsey shared his daily routine for living healthy. The episode went viral when Dorsey revealed that he eats only one meal a day (and sometimes less on weekends). But another aspect of the Silicon Valley entrepreneur’s routine is his use of light as therapy. Dorsey says he takes walks to work in the morning sun and uses infrared light bulbs and saunas. Other notable figures like NHL player Duncan Keith and supermodel Bella Hadid also say they use light therapy.

In the past few years, multiple at-home light therapy startups have launched, and mainstream beauty companies have introduced red light products. While red light therapy has all the trappings of a new health trend — it’s Instagrammable, non-invasive, and applicable to many issues — the science behind it has existed for decades.

For many people, the idea of light therapy for the mind is familiar. The most well-known example is the light box. These devices exude bright white light, which is absorbed through the retina and goes on to stimulate cells in the brain. Since the 1980s, light boxes have been used to treat seasonal affective disorder (SAD). Using light therapy for physical health is perhaps less intuitive.

Photobiomodulation therapy (PBMT) is a kind of light therapy that uses specific wavelengths of red light to penetrate tissue and stimulate cells. Studies suggest that red light therapy can speed wound recovery, relieve pain, reduce inflammation, stimulate hair growth, and treat certain kinds of acne.

Scientists still don’t completely understand the cellular and molecular dynamics underlying results like these. What they do know is that photons of red light are absorbed by an enzyme in mitochondria, the cell’s energy factory. This spurs a metabolic process that allows the mitochondria to produce more adenosine triphosphate (ATP), a molecule that fuels chemical reactions in the cell and is thought to increase a person’s energy levels.

In 1967, Hungarian physician Endre Mester accidentally discovered photobiomodulation as…