Research conducted at the University of Washington finds that sleeping at least 9 hours at night reduces body mass index (BMI).
The research was carried out through with a study on a sample of U.S. twins (1,088 pairs, 604 monozygotic, 484 dizygotic and 66% female, mean age = 36.6 yr, standard deviation = 15.9 r).
The investigation found that shorter sleep sessions are associated with increased BMI and increased genetic influences on BMI. On the other hand, increased sleep can suppress genetic influences on body weight.
When people do not sleep enough, levels of Lepitn in the body decrease. Leptin is a protein found in blood that suppresses appetite in people and when these decrease due to lack of sleep, the levels of ghrelin tend to increase. Ghrelin is a hormone that is released into the body which increases appetite in people increasing the probability for one to gain weight.
For weight control, Dr. Katie Rickel, a clinical psychologist specialist, suggested that people should keep a diary of their daily food intake recording the amount calories each food contains as well.
According to the doctor, this is the closest thing to a 'magic bullet' for losing weight.