We’ve all heard the many reasons for gaining weight, but you’ve probably not heard this one: Consistent exposure to light at night may lead to gaining weight. The odd part is that the study says that weight gain occurred even when eating habits and activity levels did not change.
The researchers found that mice who were exposed to a dim light at night over eight weeks had a body mass gain that was about 50 percent more than the mice that lived in a normal light and darkness cycle.
“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,” said Laura Fonken, lead author of the study and a doctoral student in neuroscience at Ohio State University.
The mysterious weight gain comes from what the researchers believe is ill-timed eating with the mice that were exposed to nighttime light.
“Something about light at night was making the mice in our study want to eat at the wrong times to properly metabolize their food,” said study co-author Randy Nelson, professor of neuroscience and psychology at Ohio State.
If experts can find a correlation with humans, it might at least partly explain why we get the munchies watching late night television, and why it leads to a larger waistline.