News: Light at night may lead to obesity

Are you dealing with some serious turkey-dinner regrets this morning? Well, as you consider how you’re going to burn off the extra helpings of mashed potatoes you had over the weekend, here’s some food for thought about what causes extreme weight gain (yes, pun indended): a new study suggests that exposure to light at night may lead to obesity.

The study, which will be published this week in the online edition of the Proceedings of the National Academy of Sciences, showed that mice that were exposed to dim light at night over an eight week period gained about 50 percent more weight than mice that slept in the dark.

‘Although there were no differences in activity levels or daily consumption of food, the mice that lived with light at night were getting fatter than the others,’ the study’s lead author Laura Fonken said in a press release.

One reason for the difference in weight gain, the researchers suggest, is that the mice who snoozed with light at night were prone to eating at times they normally wouldn’t.

How do these results relate to us humans? The study researchers suggest that late-night eating could be a risk factor for obesity. As well, light at night could disrupt levels of the hormone melatonin, which plays a role in metabolism.

Interestingly, the researchers have linked nighttime TV watching and computer use with increased obesity risk, not just because these activities point to a sedentary lifestyle, but because of the light emitted from the screens. 

“It may be that people who use the computer and watch the TV a lot at night may be eating at the wrong times, disrupting their metabolism,’ said study co-author Randy Nelson in that same press release.

After learning about this study, I may reevaluate my computer and TV-watching habits. Will you?

Related:
‘ 5 surprising ways you can gain weight
‘ 6 ways to rev up your metabolism
‘ Why eating at night will make you gain weight