Diet Composition Shapes Sleep, Quality of Life, and Gene Expression in Obesity: A Randomized Trial.

Obesity affects quality of life and sleep, making effective weight loss an attractive intervention. The role of diet composition on outcomes has not been determined. Our aim is to compare a ketogenic diet against an isocaloric balanced diet for effects on quality of life, sleep, circadian rhythm and gene expression in obesity. Twenty-four people affected by obesity completed the study. Volunteers were randomized to a 1200 Kcal ketogenic diet or balanced diet for 30 days, and all were encouraged to walk 30 minutes every day. Questionnaires for assessing quality of life and sleep were administered at baseline and at the end of the study. In a subgroup of 20 people actigraphy was performed to objectively capture sleep parameters, and circulating whole blood gene expression analysis was undertaken. Quality of life assessed with the IWQOL-Lite significantly improved after both diets (p<0.001), with the ketogenic diet showing a greater effect (p=0.006). The ketogenic diet also resulted in greater improvement in subjective sleep quality (p=0.023). Both diets improved daytime sleepiness (balanced diet p=0.012; ketogenic diet p=0.021). The ketogenic diet induced a greater weight loss (p=0.026). Gene expression analysis revealed greater changes in lipid metabolism with ketogenic diet. No significant changes in circadian genes were seen. Weight loss with diet intervention significantly improved quality of life of people with obesity, already after 30 days. The ketogenic diet resulted in greater improvements, in parallel with greater weight loss. Both diets influenced the expression of many metabolic genes in whole blood, with greater changes in lipid metabolism seen with ketogenic diet. Weight loss with diet intervention is effective to improve quality of life, sleep, and daytime sleepiness symptoms.