No tablets at the table. It is not just rude, research from Northwestern University suggest that before mealtime, exposure to blue light, like the type emitted by a laptop, tablet, or smartphone, may make you eat more. Fifteen minutes after being exposed to blue light, people felt an increase in hunger that lasted for two hours. Certain kinds of light can activate brain regions that regulate appetite and metabolism, says study author Phillis Zee, Ph.D. M.D. This can alter the natural rhythms of insulin and glucose production, affecting hunger as a result, she says. So switch off and eat mindfully slowing down and focusing on taste other research shows, can help your body register fullness earlier.