Ultraprocessed or minimally processed diets following healthy dietary guidelines on weight and cardiometabolic health: a randomized, crossover trial
Ultraprocessed food (UPF) consumption is associated with noncommunicable disease risk, yet no trial has assessed its health impact within the context of national dietary guidelines. In a 2 × 2 crossover randomized controlled feeding trial, 55 adults in England (body mass index ≥25 to <40 kg m<sup>-2</sup>, habitual UPF intake ≥50% kcal day<sup>-1</sup>) were provided with two 8-week ad libitum diets following the UK Eatwell Guide: (1) minimally processed food (MPF) and (2) UPF, in a random order. Twenty-eight people were randomized to MPF then UPF, and 27 to UPF then MPF; 50 participants comprised the intention-to-treat sample. The primary outcome was the within-participant difference in percent weight change (%WC) between diets, from baseline to week 8. Participants were blinded to the primary outcome. MPF (%WC, -2.06 (95% confidence interval (CI), -2.99, -1.13) and UPF (%WC, -1.05 (95% CI, -1.98, -0.13)) resulted in weight loss, with significantly greater %WC on MPF (Δ%WC, -1.01 (95% CI, -1.87, -0.14), P = 0.024; Cohen's d, -0.48 (95% CI, -0.91, -0.06)). Mild gastrointestinal adverse events were common on both diets. Findings indicate greater weight loss on MPF than UPF diets and needing dietary guidance on food processing in addition to existing recommendations. Clinicaltrials.gov registration: NCT05627570 .
Authors
- Ritwika Mallik
- Craig Ranson (ORCID: https://orcid.org/0000-0002-3783-0505)
- Janine Makaronidis (ORCID: https://orcid.org/0000-0003-1045-2871)
- Sulmaaz Qamar
- Abigail Fisher (ORCID: https://orcid.org/0000-0001-9284-6780)
- Friedrich C. Jassil (ORCID: https://orcid.org/0000-0002-9721-7665)
- Jonathan M. Bird (ORCID: https://orcid.org/0000-0003-3929-8783)
- Claudia A. M. Gandini Wheeler‐Kingshott (ORCID: https://orcid.org/0000-0002-4832-1300)
- Samuel J. Dicken (ORCID: https://orcid.org/0000-0001-5663-1715)
- Martins Kalis
- Tinashe B. Ruwona
- Mark Hamer (ORCID: https://orcid.org/0000-0002-8726-7992)
- Kevin D. Hall (ORCID: https://orcid.org/0000-0003-4062-3133)
- Caroline Buck (ORCID: https://orcid.org/0000-0002-6663-3842)
- Adrian Brown (ORCID: https://orcid.org/0000-0003-1818-6192)
- Chris van Tulleken
- Benjamin Norton (ORCID: https://orcid.org/0000-0003-2058-3162)
- Rachel L. Batterham (ORCID: https://orcid.org/0000-0002-5477-8585)
- Alanna Kathleen Brown (ORCID: https://orcid.org/0000-0002-0104-3251)
- Nasser Hamid
- C Stanley
Institutions
- University College Hospital (GB)
- English Institute of Sport (GB)
- University of East London (GB)
- Barts Health NHS Trust (GB)
- University of Pavia (IT)
- National Institute for Health and Care Research (GB)
- Fondazione Istituto Neurologico Nazionale Casimiro Mondino (IT)
- University Hospital of Geneva (CH)
- Kensington Health (CA)
- World Obesity Federation (GB)
- The London College (GB)
- Cleveland Clinic London (GB)
- National Hospital for Neurology and Neurosurgery (GB)
- University College London (GB)
Publication Details
- Journal
- Nature Medicine
- Published
- 2025-08-04
- DOI
- https://doi.org/10.1038/s41591-025-03842-0
- Citations
- 43
- Primary Topic
- Consumer Attitudes and Food Labeling
- Type
- article
- Field-Weighted Citation Impact
- 80.78
Funders
- Cleveland Clinic
- British Dietetic Association
- National Institute for Health and Care Research
- British Heart Foundation
- Ataxia UK
- Society for Endocrinology
- Rosetrees Trust
- University College London Hospitals NHS Foundation Trust
- National Institutes of Health
- Medical Research Council
- National Institute of Diabetes and Digestive and Kidney Diseases