Long daytime naps may be an early warning sign for type 2 diabetes A meta-analysis from the University of Tokyo has suggested that napping during the day for more than hour may be an early warning sign of type 2 diabetes. The researchers analyzed 21 observational studies involving more than 300,000 people and found an association between daytime naps longer than an hour and a 45% increased risk for type 2 diabetes compared with no daytime napping. While, shorter naps had no effect on the risk of diabetes. But there was no evidence to suggest a ‘cause and effect’ association between napping and type 2 diabetes. The results of the study were presented at the 52nd European Association for the Study of Diabetes meeting EASD 2016 in Munich, Germany.