Here's an odd theory: Researchers at Oxford say one explanation for obesity might be … excessive light in our bedrooms. They aren't yet certain enough to advise a darkness boost, but a study in the American Journal of Epidemiology found that women had larger waistlines if their bedrooms were "light enough to see across" after dark, the BBC reports. Some 113,000 women reported the amount of light in their rooms (enough to read by? enough to see close-up or far away?), and researchers compared those results with body-mass index, waist circumference, and other measures.
It could be that light in the bedroom messes with our body clocks, affecting how our bodies handle food. "We cannot yet tell at this stage what the reason for the associations is, but the results open up an interesting direction for research," one researcher says in the Telegraph. Over the past century, our rooms have been getting lighter, an expert on the history of homes tells the BBC in a separate story. There are more streetlights and neon signs outside, and we've begun to prefer thinner curtains and white paint. We also have all kinds of devices whose standby lights stay on all night. (Click to read about another new study that shows how our brain creates memories while we sleep.)