Renate E.H. Meeusen¹, Karlijn A.M. Geurts¹, Kirsten A.C. Berk¹, Elisabeth F.C. van Rossum¹

¹Department of Internal Medicine, Division of Endocrinology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands

Rationale: A higher intake of ultra-processed foods (UPF) is associated with obesity. This study examines the association between UPF intake and both biological and perceived stress levels and eating behaviour in people with obesity following a 1.5 year combined lifestyle intervention (CLI).

Methods: Data of 121 adults with obesity participating in a CLI with cognitive behavioural therapy at the academic Obesity Centre CGG, Rotterdam, The Netherlands was collected at start, 10 weeks and 1.5 years. Food intake was obtained by a 3-day food diary. To quantify UPF intake, the records were classified into four NOVA categories. The percentage of energy consumed from the UPF categories compared to the total energy consumed was calculated. Both biological (cortisol and cortisone in hair) and perceived (questionnaire Perceived Stress Scale) stress levels were measured. Eating behaviour was assessed using the Dutch Eating Behaviour Questionnaire and the General Food Craving Questionnaire Trait. Marginal mixed models were performed to explore associations between UPF intake and the outcomes at all three timepoint, corrected for age and sex.

Results: UPF intake decreased from 57.5% at baseline to 52.8% after 1.5 years of CLI, while an increase from 29.0% to 35.9% in unprocessed food intake was observed (both p<0.02). UPF intake was associated with perceived stress scores (estimate=0.085, p=0.007) and remained constant over time. Emotional eating and external eating were positively associated (estimate=0.007 and 0.006, respectively, both p<0.05) and these associations did not change over time. Restrained eating behaviour was negatively associated with UPF intake (estimate=-0.009, p<0.001) and showed a significant interaction over time (p=0.004). No associations were observed between UPF and biological stress measures and food cravings.

Conclusion: Less ultra processed foods and more unprocessed foods were consumed during the CLI. Lower UPF intake was associated with decreased perceived stress levels, less emotional- and external eating and more restrained eating.