How light pollution affects our health
When we think about light pollution we think about the glow that streetlights cast above our villages, towns, and cities. This sky-glow often extends far into the countryside, and has an impact on both plants and animals, which rely on the phases of the day to know when to hunt, eat, and sleep. We humans are affected by light pollution in similar ways.
Artificial light has brought many benefits, but when that light becomes intrusive, annoying, and unnecessary it is known as light pollution. This light pollution can have serious, and sometimes lasting, effects on our own health. While CPRE agrees that some of this light is necessary, much of it is wasting energy, shining upwards where it isn’t needed, spilling into homes, disrupting people’s sleep and affecting the behaviour of wildlife.
The 24 hour day/night cycle that we live by is known as the circadian cycle, and it’s this which controls processes in almost all living things, including metabolism, growth and mood. Prolonged exposure to light pollution can lead to conditions like depression, sleeplessness, and heart and blood problems. The day-to-day effects of light pollution that many of us may unknowingly suffer from are those that affect our sleep – we might start to feel tired during the afternoon, longing for a quick nap at work or in school! Similarly, we may find ourselves unable to sleep until quite late at night, which is known as delayed sleep–phase syndrome.
The quality of our lives and natural world is being diminished by light pollution, yet there are simple things that can be done to ensure light shines only where and when it is needed. We can also turn unneeded lights off and we can fit blackout curtains that will help keep as much unwanted light out of our homes as possible when appropriate. It may seem harder to affect the overall light pollution in our towns, but we can contact our local councillors or MPs to ask them to look into using better-designed public lighting, which perhaps only comes on when sensors detect passers-by. We can also ask local businesses to commit to turning off office lights and outdoor lights at night.