Sunlight has a range of wavelengths, and these have been classified into four main groups: ultraviolet, visible, near infrared and far infrared. We can see the light in the visible spectrum (red, orange, yellow, green, blue indigo, violet) but we can't see ultraviolet light and neither can we see infrared light.

Much research has been done on the effect of the sun's ultraviolet light. It can cause premature ageing and increases the risk of skin cancers, hence the warnings to wear sunscreen to block those wavelengths from hitting the skin.

Until recent years, the effect of red and near infrared light, had been of less interest to medical science. It is now an area of increasing research, and the implications seem to be huge.

In 2015 an article with the rather daunting title Light Effect on Water Viscosity: Implications for ATP Biosynthesis, appeared in the journal Nature. It gave a very detailed description of the mechanism by which near infrared light can change the way that cells function.

Over the decades, there had been reports about the effectiveness of red and near infrared light on a range of medical conditions, but it was not taken terribly seriously in the early days. It seemed too good to be true.

• How could shining a red/near infrared light onto a wound make it heal more rapidly?

• How could shining red/near infrared light onto your head improve symptoms of depression, anxiety, Parkinson's Disease or Alzheimer's Disease?

• How could shining red/near infrared light onto arthritic joints and sore muscles improve the joint and muscle function, and reduce pain?

I certainly was sceptical. The disdain started to dissipate on finding that there are good quality peer-reviewed medical research articles consistently showing that red/near infrared light had very desirable health effects in a range of different diseases.

Miserable mitochondria could be the fundamental problem in many diseases...

It is looking like many of the diseases, however they start and whichever part of the body they target, all end up with a common problem - poorly functioning mitochondria.

• Give the miserable mitochondria a burst of red/near infrared light, and they fire into action. For a while. Give them another burst, and they fire up again.

• Give the miserable mitochondria regular (eg twice daily) bursts of light, and the cell is able to function effectively on a day to day basis.

There is so much more to tell. The research findings are flooding in.

Keep tabs on this blog as it explores the medical literature on red and near infrared light.