Over nine million Chinese could be diabetic due to excessive exposure to artificial light at night: this is the conclusion reached by a study conducted on almost one hundred thousand people and published in the journal Diabetes, which disturbs but does not surprise. In fact, scientific literature has been dealing with the harmful effects of artificial light on plants, animals and humans for years: the results of Chinese research only confirm that light pollution affects our health in various ways.
Bad for everyone. Artificial night light (light at night, LAN) alters the circadian rhythm of insects, birds and other animals, which often die prematurely. But in addition to having direct negative effects on the life and survival of animals, LAN also acts on plants, lengthening the pollen season.
Light pollution also directly damages the human body: those who work at night, for example, run a greater risk of suffering from coronary heart disease; in another study, exposure to artificial light was associated with a 13% and 22% increased likelihood, respectively, of being overweight or obese; furthermore, LAN exposure in the bedroom is correlated with the development of diabetes in older people.
At risk of diabetes. If it is true that we are always dealing with correlated events, and not causal ones (i.e. not linked by a cause-effect relationship), to quote Ian Fleming one could say that once is chance, twice is coincidence, three times is enemy action. And the researchers’ study represents yet another proof against the enemy-LAN: the sample of volunteers is quite large and heterogeneous, made up of half women and half men, with an average age of about 43, coming from 162 different areas of China. The results showed that the prevalence of diabetes was significantly higher (+28%) in citizens more exposed to external LAN than in those less exposed, and that those who lived in the regions with the best light at night had one more case of diabetes for every 42 people compared to those who lived in darker places.
‘Although more than 80% of the world‘s population is exposed to nocturnal light pollution, this problem has not attracted much interest from scientists until recent years,’ the authors write, emphasizing the need for further studies to confirm that the diabetes-light pollution link is not simply accidental.