Gradual Sleep Deprivation, Obesity and Cognitive Impairment

By get­ting less than our required amount of sleep over an exten­ded peri­od of time (two weeks, for example) we are increas­ing our risk of obesity and impair­ing our cog­nit­ive abil­it­ies without even being aware of it.

That’s the con­clu­sion from a short art­icle sum­mar­ising the sur­pris­ing effects of gradu­al sleep depriva­tion:

Research­ers […] restric­ted volun­teers to less than six hours in bed per night for two weeks. The volun­teers per­ceived only a small increase in sleep­i­ness and thought they were func­tion­ing rel­at­ively nor­mally. How­ever, form­al test­ing showed that their cog­nit­ive abil­it­ies and reac­tion times pro­gress­ively declined [until] they were as impaired as sub­jects who had been awake con­tinu­ously for 48 hours.

Moreover, […] too little sleep changes the body’s secre­tion of some hor­mones. The changes pro­mote appet­ite, reduce the sen­sa­tion of feel­ing full after a meal, and alter the body’s response to sug­ar intake—changes that can pro­mote weight gain and increase the risk of devel­op­ing dia­betes. […]

A recent review […] of the large stud­ies that fol­lowed people over time agreed that short sleep dur­a­tion was asso­ci­ated with future weight gain. […] For example, [one study] showed an inverse cor­rel­a­tion between sleep dur­a­tion and obesity in high-school-age stu­dents. The short­er the sleep, the high­er the like­li­hood of being over­weight, with those get­ting six to sev­en hours of sleep more than two and a half times as likely to be over­weight as those get­ting more than eight hours. […]

The good news is that these effects can be reversed by get­ting an adequate amount of sleep. […] Allow­ing the study sub­jects to sleep 10 hours for two con­sec­ut­ive nights returned the hor­mones to nor­mal levels and lowered hun­ger and appet­ite rat­ings by almost 25 per­cent.

via @finiteattention