How Does Sleep Affect Your Weight - as part of the expert series by GeoBeats. Sleep can affect your weight maintenance based on two really important hormones in your body. There is a hormone called ghrelin, which is the go hormone, which tells your body to eat, and then there is another hormone called leptin, which tells your body to stop eating. What research has shown is that when you are sleep deprived, and that means typically less than around seven, seven and a half hours a night, your body produces more ghrelin, so your body is telling you to eat more. So research really tells you that to really keep those hormones at bay, and to keep them balanced, you need to have at least seven to seven and a half hours of sleep per night.