This is one of the conclusions of the Predimed-Plus study, Prevention with the Mediterranean Diet, which has been published in the June issue of the International Journal of Obesity. It is the first study to examine whether the quality of sleep is related to weight loss and a reduction in adipose tissue.
In their study, the researchers from the Human Nutrition Unit of the Rovira i Virgili University, in conjunction with other research groups involved in the Predimed-Plus study, assessed the changes in weight and adiposity - body fat - of the 1,986 individuals who took part in the study for a whole year, all of whom presented overweight, obesity and the metabolic syndrome. The patients followed an intensive intervention programme in terms of lifestyle designed for weight loss. It was based on a low-calorie Mediterranean diet, physical activity and behaviour therapy. The researchers observed that the individuals with highly variable sleep patterns - that's to say, who did not sleep the same number of hours every night - at the beginning of the study lost less weight after a follow-up period of 12 months. What is more, a high sleep variability and sleeping little - less than six hours - a day was associated with a lower decrease in body mass index and waist circumference.
These results reveal that adopting measures to achieve an appropriate sleep pattern may have an impact on maintaining the correct weight and preventing other metabolic disorders associated with excess body fat.
The study was led by Christopher Papandreou, principal investigator of the Human Nutrition Unit of the URV's Department of Biochemistry and Biotechnology, and Jordi Salas-Salvadó, head of the Unit, director of clinical nutrition of the Internal Medicine Service of the University Hospital Sant Joan in Reus and principal investigator of CIBERobn. They are both members of the Pere i Virgili Institute for Health Research (IISPV)