Above: Sun rise at the Trundle, Goodwood, West Sussex – © Keir Watson, 2010
Dawn, dusk, midday. Sunlight cheers the spirits like nothing else. As in the ancient civilisations of South America and Egypt, we all worship the sun in our own way: sunbathers prostrate themselves before it, at bank holidays we pray for its arrival, and everyone simply feels better when the sun is shining.
This urge is natural and healthy. Man evolved in central Africa where there was no lack of sunshine. Moreover, as he left the forests he developed hairless skin, exposing his body more fully to the direct rays of the sun. For millions of years he spent the majority of his day outdoors. Furthermore, as humans moved north to less sunny climates a mutation occurred – white skin – an adaptation that persisted as it allowed better synthesis of vitamin D in regions where the sun was weaker.
It is not surprising then, that there are many aspects of our physiology that are dependent on light. Like the orchids in the picture above, humans too photosynthesise. Not only does sun falling on skin produce vitamin D – an essential hormone – but recently it has been shown that it promotes the release of nitric oxide into the capillaries leading to a lowering of blood pressure*. Another effect comes from the red light of morning and evening which act on the skin, eyes and brain regulating the circadian rhythm and ensuring a good sleep-wake cycle.
A vast body of research is now emerging linking different parts of the spectrum, including ultraviolet and infra-red to a range of health processes. The application of this knowledge is called phototherapy. As most of us now live indoors for the majority of the time, and expose ourselves to artificial light such as fluorescent lights and computer screens late into the evening, an understanding of light and health is becoming ever more urgent. In the articles below I will explain some of the ways that I use phototherapy in my clinic, but will also share some ideas you can easily put into practise for yourself.
This is my UVB narrowband lamp unit. It is wall mounted, and housed in a cupboard which I had specially made for it. Patients stand in front of the lamps to receive a dose of UVB to the torso – front back and/or sides, arms, or by raising them one at a time on a chair – the legs. Goggles must be worn as UV is damaging to the eyes.
The lamps are medical narrow-band (311 nanometer) UVB fluorescent tubes. This is the wavelength at which vitamin D production is maximised (shown as green on diagram opposite) whilst the harmful effects of UV light are minimised (red on diagram).
Although you can see some visible light in the picture above, 99% of the energy is invisible UVB. These are not tanning lights. Tanning salons use UVA broad spectrum tubes – an entirely different class of equipment that has little medical value and carries significant risk.
I use my lamps to treat vitiligo, psoriasis and similar skin disorders, for which UV therapy is a recognised treatment, as well as vitamin D insufficiency. In our Northern European climate there are very few days in the summer when we produce sufficient vitamin D, and throughout the late autumn, winter and spring the sun – even at midday- is too weak to produce any vitamin D. Yet vitamin D levels can be increased to or maintained at summer levels using my lamp with as little as 2 minutes treatment per week, depending on your skin colour.
My red light box is a portable table-top unit, with fold out wings, and can be angled to illuminate the face. Goggles do not need to be worn as the light is not bright enough to damage the eyes. In deed, there is evidence that red light is beneficial for the retina. About 20 years ago, NASA demonstrated effective pain relief using red light in paediatric cancer patients. Since then many studies have demonstrated not only the pain-relieving effects of red light, but also a role in increased wound healing, stimulating hair re-growth, and synthesis of collagen in the skin.
Red light penetrates the skin a few millimetres, reaching superficial blood vessels and muscles. Interestingly, it has been shown to stimulate the production of mitochondria in cells, and has been used by athletes to increase endurance and recovery.
My unit can be placed on the floor to treat the feet and legs, or on a chair to treat the back. It has a built in timer, and needs to be used daily for ten minutes or more, depending on the condition being treated. For patients that need it I am able to lend the unit out for them to try before purchasing their own if they wish. (Note: I do not sell these units)