Unnatural Sleep Schedules Can Make You Fat People who disrupt biological clocks have higher BMIs By Dustin Lushing, Newser Staff Posted May 11, 2012 3:40 PM CDT 6 comments Comments Ignoring your natural sleep cycle can result in a little excess baggage. (Shutterstock) (Newser) – Your alarm clock could be making you flabby, suggests new research. People who force themselves to maintain schedules that are different from their natural sleep routines are more likely to put on the pounds, reports LiveScience. Researchers collected data from more than 65,000 Europeans and found that for every hour of sleep discrepancy between their work days and free days, the person was 33% more likely to have a higher BMI, a measure of fatness. "We are biological beings, and we have a biological clock, and what society—and I don't mean the bad guys, I mean all of us—is ignoring is the biological clock," says an author of the study. Night owls are affected the most. "If you are awake at night, there is a good reason from an evolutionary perspective, something has to be going on," says another sleep researcher. The body thinks it will need energy and thus craves food high in fat and sugar.