Poster Presentation Australian and New Zealand Obesity Society Annual Scientific Conference 2024

What is the effect of non-ketogenic, diet-induced weight loss on appetite markers in adults with overweight and obesity? A systematic review and meta-analysis (#261)

Jessica Roekenes 1 , Anna S Lyngstad 1 , Hamish Fernando 2 , Helen Truby 3 , Amanda Sainsbury-Salis 4 , Mette Svendsen 5 , Catia Martins 6
  1. Department of Clinical Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
  2. Faculty of Engineering, University of Sydney, Sydney, Australia
  3. School of Human Movement and Nutrition Sciences, University of Queensland, Brisbane, Australia
  4. School of Human Sciences, University of Western Australia, Perth, Australia
  5. Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital, Oslo, Norway
  6. Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama, USA

Objectives: Evidence regarding the association between diet-induced weight loss (WL) and appetite-related markers remains controversial. This systematic review and meta-analysis aimed to conduct a critical appraisal of the effect of diet-induced WL, outside of ketosis, on appetite markers.

Methods: Systematic searches were performed for randomized and non-randomized controlled trials that employed non-ketogenic dietary interventions (outside of ketosis) on adults (>18 years, BMI≥ 25/m2) using energy restriction that yielded a WL ≥2 kg over <7 days. Studies needed to use a within-subject repeated measures design and provide outcomes of appetite-related hormones (ghrelin, glucagon-like peptide 1 (GLP-1) , peptide YY (PYY), and cholecystokinin) and/or appetite feelings (hunger, desire to eat, prospective food consumption, satiety, and fullness) that were assessed pre-and-post WL. Study searches were adapted to satisfy each database.

Results: 6,553 articles were retrieved from databases PubMed, (Pre)Medline, EMBASE, SCOPUS, Central (COCHRANE) and Epistemonikos. 51 articles (87 comparison arms) were included in the meta-analysis and 18 were reviewed qualitatively. The meta-analysis compared standardized mean differences in appetite markers taken pre-and-post WL. Studies yielded an average WL of 6.9±3.9 kg. For appetite-related hormones: there were trends toward increases in basal total and active ghrelin, postprandial active ghrelin, and decreases in basal active GLP-1, basal PYY, basal and postprandial CCK concentrations. For appetite-related feelings, there were trends toward increases in hunger, desire to eat and prospective food consumption measured in fasting, and fullness and satiety measured after a meal. No significant changes were found for all other appetite-related hormones and their fractions. Large methodological and statistical heterogeneity was found among the studies.

Conclusion: Studies showed trends towards increases in hunger, DTE and ghrelin and decreased concentrations of satiety hormones following WL. More comprehensive studies are warranted to confirm these findings due the variety of dietary intervention employed and limited number of studies measuring hormonal fractions.