Light emitted by phones or tablets at night causes sugar cravings and could lead to weight gain, a study on rats has shown. Just one hour of exposure to blue light – the artificial light given off by technology –was found to affect the rat's appetite and make it more likely to eat unhealthy food the next day. Their blood sugar levels also shot up, suggesting the animals were unable to process the sugar in their body, a warning sign of pre-diabetes. It's the latest in a slew of damning evidence against using phones too much at night – scientists have said in the past it could lead to obesity.
The study by the University of Strasbourg and University of Amsterdam, was presented at the annual conference of the Society for the Study of Ingestive Behavior (SSIB) in Utrecht, Netherlands, this week.
Previous research has shown a link between obesity and the levels of artificial light someone sees at night. The biological mechanisms which lead to a higher appetite or glucose intolerance are not explained, but are believed to be due to an alteration in hormones. Other research, which found women who fell asleep with the light or TV on weighed more than those who did not, led to scientists suggesting limitation of artificial light could be used as an intervention for obesity.
