80 % increased prostate cancer risk with artificial light

In the west, we take for granted that we can have light all day and night – and in our cities we are never away from artificial light. Now, a new study at the University of Haifa, reported on 4 February, 2009, has discovered that countries with the highest levels of artificial light at night also have the highest rates of prostate cancer. This is found worldwide, and confirms previous studies at Haifa that found a connection between exposure to artificial light at night and the incidence of breast cancer.

They studied a database on cancer incidence in men in 164 countries and even at the early stage of the study it was apparent that there is a marked link between the incidence of prostate cancer and levels of artificial illumination at night. Countries with low exposure to such light showed an incidence of prostate cancer of 66.77 patients to 100,000 inhabitants. An increase of 30% was found in those countries with medium exposure, and those countries with the highest level of exposure to artificial light at night shoed a huge leap of 80%: with 157 patients per 100,000 inhabitants.

There could be many reasons for this increase; with high levels of light melatonin production is reduced and this affects our immune system and our own internal biological body clock gets affected as it cannot distinguish between night and day.

It’s not just health that is affected by artificial lighting either. The World Health Organization regards it as a serious source of environmental pollution, so our city planners may need to take this into account in future. On a personal level, turn the lights out at night, and don’t have electronic devices in the bedroom which use lighting such as clocks, televisions and video games.