Researchers from Columbia University have found that even a slight but regular reduction in sleep duration can lead to weight gain and increase the risk of obesity-related diseases. The results of the study are reported by the Daily Mail. About one hundred adult volunteers who typically slept seven to eight hours a day participated in the experiment. Half of the participants were asked to reduce their nightly sleep by about 80 minutes every day for six weeks. To closely mimic real-life conditions, the volunteers went to bed later than usual but woke up at their regular time. After six weeks, it was found that participants who regularly experienced sleep deprivation gained an average of nearly half a kilogram, while the weight of those in the control group changed little. Additionally, researchers discovered that subjects who slept less engaged in physical activity for nearly 20 minutes less each day, even though they had more waking hours. Previously, scientists had already proven that severe sleep deprivation contributes to obesity. However, the new study showed for the first time that even relatively small daily sleep deprivation can be dangerous. "Although a weight gain of about half a kilogram due to moderate sleep reduction cannot be considered significant, it is important to understand that this result was achieved in just six weeks," noted the lead author of the study, dietitian Faris Zuraikat. According to him, the experiment was specifically designed to replicate the typical sleep patterns of most adults who are chronically sleep-deprived. "If these data are extrapolated over a year, one can expect that losing less than an hour and a half of sleep each night will lead to clinically significant weight gain," the scientist explained. Researchers are still unable to confidently identify the mechanism causing rapid weight gain, but they suggest that chronic sleep deprivation disrupts hormonal balance. In particular, it affects the levels of hormones that regulate hunger and appetite, causing individuals to consume more food. "Our study shows that adequate sleep can reduce the risk of weight gain and obesity-related diseases, including heart disease and diabetes," emphasized the study leader, dietitian Marie-Pierre St-Onge. The authors of the study believe that a full night's sleep is one of the most important factors in maintaining health. Regular sleep deprivation can not only contribute to weight gain but also increase the risk of cardiovascular diseases, diabetes, and other metabolic disorders.