Have you ever thought about sleeping in but were afraid you would gain weight because of the added inactivity? It has occurred to me on more than one occasion. I mean, doesn’t it make some sort of sense that the longer you periods of inactity are (as in sleeping) the more you would tend to put on a few extra pounds?
Well, it turns out that sleeping in a few days a week does not make you fat. Accoording to a new study published just last week, sleeping more than nine hours a night (sheer heaven!) might trun off genetic mechanisms that predispose you to gain weight. In other words–you can lose weight by sleeping!
Here is what the study found:
The study looked at 1,088 pairs of twins and found that sleeping less than seven hours a night was associated with both increased BMI and greater genetic influences on BMI. Previous research has shown that genetic influences include things like glucose metabolism, energy use, fatty acid storage and satiety. In this study, the heritability of BMI was twice as high for the short sleepers than for twins who slept longer than nine hours a night.
“The results suggest that shorter sleep provides a more permissive environment for the expression of obesity related genes,” said principal investigator Nathaniel Watson, MD, MSc, of the University of Washington. “Or it may be that extended sleep is protective by suppressing expression of obesity genes.”
Watson and colleagues determined that for twins sleeping less than seven hours, genetic influences accounted for 70 percent of the differences in BMI, with common environment accounting for just 4 percent and unique environment 26 percent. For twins averaging more than nine hours of sleep, genetic factors were attributed to 32 percent of weight variations, with common environment accounting for 51 percent and unique environment 17 percent.
While these are only tentative results, they are very encouraging ones for those of us that have resolved some of our sleep issues and may feel the occasional tinge of guilt. Or, at least for those of us who are taking sedating medications to help us get the sleep we need, it can make us feel a little more at ease. It has made me feel less guilty on those rare days when I can actually sleep in! Yes, it seems you can actually lose weight by sleeping.
