Sleeping for more than nine hours may help weight loss: research The findings were published in the journal, Sleep. Lead author Dr Nathaniel Watson, said: "The results suggest that shorter sleep provides a more permissive environment for the expression of obesity related genes. Or it may be that extended sleep is protective by suppressing expression of obesity genes. Dr Watson said the results were preliminary but may suggest that weight loss measures would be most effective when the genetic influences on obesity were mitigated through sleep extension.