Can the ketogenic diet improve our dreams? Effect of very low-calorie ketogenic diet (VLCKD) on sleep quality

Abstract

Abstract Background Obesity is a condition that is often associated with sleep disorders, including reduced sleep quality (SQ). Very low calorie ketogenic diet (VLCKD) has proven to be effective in the management of obesity and associated metabolic disorders. However, little is still known about the effects of this promising nutritional protocol on SQ. Thus, the purpose of this study was to investigate the short-term effect of VLCKD on SQ in women with overweight/obesity and if any changes, to identify the predictive factor that through VLCKD modified SQ. Methods Were consecutively enrolled a total of 324 subjects, who met the inclusion criteria and accepted to adhere to VLCKD. Assessment of nutritional status, including anthropometric measurements (height, weight, and waist circumference), bioelectrical impedance analysis (phase-sensitive system, 50 kHz BIA 101 RJL, Akern Bioresearch, Florence, Italy Akern), high sensitivity C reactive protein levels (hs-CRP), and SQ were carried out at baseline and after 31 days of active stage of VLCKD. SQ was evaluated using the validated questionnaire Pittsburgh Sleep Quality Index (PSQI). Results In addition to the expected general improvement of anthropometric parameters and body composition, VLCKD improved significantly SQ, as demonstrated by the improvement of all parameters included in the PSQI questionnaire (p − 8.4% predicted improvement in SQ (p < 0.001). Conclusion In conclusion, VLCKD determines an improvement of SQ in women with overweight and obesity, that was mostly mediated by the reduction of fat mass related to this nutritional protocol. Graphical Abstract

Keywords

• Sleep quality
• Obesity
• Very low-calorie ketogenic diet
• VLCKD
• Ketogenic diet
• Fat mass