15th December 2020 marks the 160th birthday of Niels Ryberg Finsen, who won the Nobel Prize for his work exploring the use of light radiation in medicine.

Born in the Faroe Islands to Icelandic and Danish parents, Finsen (1860-1904) was a pioneer of the use of light, particularly in the treatment of lupus vulgaris, a painful skin condition related to tuberculosis.

As well aiding patients through light therapy, Finsen’s work also demonstrated the widespread health benefits of different wavelengths of light, including its antimicrobial properties.

In many ways, his work helped pave the way for the widespread use of UV-C as a method of disinfecting and sterilising harmful pathogens, which we use it for today.

Himself suffering from a chronic illness, Niemann-Pick disease, Finsen became fascinated with the health properties of sunlight.

“My disease has played a very great role for my whole development… The disease was responsible for my starting investigations on light: I suffered from anaemia and tiredness, and since I lived in a house facing the north, I began to believe that I might be helped if I received more sun. I therefore spent as much time as possible in its rays. As an enthusiastic medical man I was of course interested to know what benefit the sun really gave.” – Niels Ryberg Finsen

Finsen’s studies primarily concerned phototherapy, also known as heliotherapy or light therapy. This technique makes use of the health benefits of exposure to specific wavelengths of light, using polychromatic polarised light to treat skin conditions.

One of its most common usages today is in the treatment of seasonal affective disorder (SADS) and in circadian rhythm disorders and it can also be used to treat depression and bipolar disorder as well as skin problems.

Finsen was convinced that light could bring a wide range of health benefits to organisms and he devised phototherapeutic treatments for small-pox and lupus which made use of concentrated light produced by chemical reactions, similar to the reactions used for modern ultraviolet lights.

As well as demonstrating the general stimulating effects of light on organic tissues, Finsen also showed that light also has bactericidal properties; leading the way toward the use of UV-C radiation for surface and air disinfection.

Already a professor and a Knight of the Order of Dannebrog in recognition of the importance of his discoveries, Finsen was awarded the Nobel Prize in Physiology or Medicine in 1903. He also received a Danish gold medal for merit and the Cameron Prize from the University of Edinburgh shortly before his death in 1904.

The Nobel Prize in Physiology or Medicine 1903 was awarded to Niels Ryberg Finsen “in recognition of his contribution to the treatment of diseases, especially lupus vulgaris, with concentrated light radiation, whereby he has opened a new avenue for medical science.”

To find out more about how we use the germicidal properties of ultraviolet light, as demonstrated by Finsen, click here.