Relation between dietary inflammatory potential and sleep features: Systematic review of observational studies

Article type: Review Article

Authors: Godos, Justyna^{a; *} | Lanza, Giuseppe^{b; c} | Ferri, Raffaele^d | Caraci, Filippo^{e; f} | Cano, Sandra Sumalla^{g; h; i} | Elio, Iñaki^{g; h; j} | Micek, Agnieszka^k | Castellano, Sabrina^l | Grosso, Giuseppe^{a; m}

Affiliations: [a] Department of Biomedical and Biotechnological Sciences, University of Catania, Catania, Italy | [b] Department of Surgery and Medical-Surgical Specialties, University of Catania, Catania, Italy | [c] Clinical Neurophysiology Research Unit, Oasi Research Institute-IRCCS, Troina, Italy | [d] Sleep Research Centre, Oasi Research Institute-IRCCS, Troina, Italy | [e] Department of Drug and Health Sciences, Universityof Catania, Catania, Italy | [f] Neuropharmacology and Translational Neurosciences Research Unit, Oasi Research Institute-IRCCS, Troina, Italy | [g] Research Group on Food, Nutritional Biochemistry and Health, Universidad Europea del Atlántico, Isabel Torres, Santander, Spain | [h] Universidad Internacional Iberoamericana, Campeche, México | [i] Universidad de La Romana, LaRomana, República Dominicana | [j] Fundación Universitaria Internacional de Colombia, Bogotá, Colombia | [k] Statistical Laboratory, Faculty of Health Sciences, Jagiellonian University Medical College, Kraków, Poland | [l] Department of Educational Sciences, University of Catania, Catania, Italy | [m] Center for Human Nutrition and Mediterranean Foods (NUTREA), University of Catania, Catania, Italy

Correspondence: [*] Corresponding author: Justyna Godos, Department of Biomedical and Biotechnological Sciences, University of Catania, 95123 Catania, Italy. E-mail: [email protected].

Abstract: BACKGROUND:Diet and sleep represent key behavioral risk factors for major non-communicable diseases. Dietary factors may modulate systemic inflammation and potentially affect the human brain functionality, finally affecting the sleep-wake cycle. In this context, the Dietary Inflammatory Index (DII) has been studied as a tool to investigate the dietary inflammatory potential and its relationship with a variety of health conditions. OBJECTIVE:The aim of this study was to perform a systematic revision of observational studies on the inflammatory potential of the diet assessed through the DII and sleep features. METHODS:A systematic search of observational studies on DII and sleep features was conducted on Pubmed and EMBASE electronic databases. The Meta-analyses Of Observational Studies in Epidemiology (MOOSE) guidelines were used to plan the methodology. Studies identified through the search were selected according to inclusion/exclusion criteria. RESULTS:The systematic search and review led to the selection of 13 studies. Most studies including the general population reported an association between higher inflammatory potential of the diet and worse sleep quality and suboptimal sleep duration. Some studies also reported an association with daytime sleepiness and sleep apnea. However, some studies including younger individuals (i.e., college students or young employees) reported null findings. Four studies conducted in individuals with a variety of health conditions also showed some relation between DII and sleep features, although results were not fully consistent. CONCLUSIONS:Data published so far suggests an association between DII and sleep features. However, lack of randomized clinical trials and better designed observational studies, imply that further research on this matter is warranted to understand whether a causal relation could explain current findings.

Keywords: Dietary inflammatory index, diet, inflammation, sleep quality, sleep duration, insomnia, daytime sleepiness

DOI: 10.3233/MNM-240008

Journal: Mediterranean Journal of Nutrition and Metabolism, vol. 17, no. 1, pp. 1-14, 2024