Randomised controlled trialindependent cross-checkabstract checked I-UPF-102 in-depth review

Eating speed and ultra-processed diets

Eating rate has sustained effects on energy intake from ultraprocessed diets: a 2-week ad libitum dietary randomized controlled crossover trial.

Overview

Forde CG et al.. Am J Clin Nutr 2026 · PMID 41314613 · DOI 10.1016/j.ajcnut.2025.11.012

When ultra-processed meals were chosen to be eaten slowly, people ate about 370 kcal less per day than with fast-to-eat ultra-processed meals.

Does the study support the specific claim? Partly · Methodological quality: high

Study explained simply

What did the researchers want to find out?: To test whether eating rate drives intake on UPF diets.
How was the study done?: Randomised crossover trial, 2 weeks per diet.
How many people, animals or samples were studied?: 41 young adults.
What was actually found?: Slower-to-eat UPF meals reduced intake; weight unchanged.
How large was the observed effect?: -369 kcal/day (221-517).
What do the results mean in everyday life?: How fast food is eaten matters, not only whether it is processed.
What are the study's limitations?: Short; healthy young adults; industry ties of first author.
What does it say about Elawady's specific claim?: Qualifies C-UPF-02.
Do the results apply to Germany and Europe?: Applicable.
What can explicitly not be concluded from this study?: Cannot show that UPF is harmless.

Authors: Forde CG et al.
Journal: Am J Clin Nutr
Year: 2026
Identifier: PMID 41314613 DOI 10.1016/j.ajcnut.2025.11.012 · PMC13084570
Verification: verified – PubMed efetch 2026-10-26; Crossref works API 2026-10-26
Retracted: no
Corrections: none
Extent checked: abstract only
Conflicts of interest and funding: COI statement in record: Conflict of interest CGF is a member of the Global Independent Nutrition Advisory Board of Lesaffre; reports a relationship with Kerry Taste and Nutrition that includes travel reimbursement; reports travel reimbursements from USDA, International Life Sciences Institute, Ajinomoto Co. Inc, British Nu

Does meal texture-derived eating rate change energy intake from UPF diets?

Study design: Randomised controlled trial – Single-blind, block-randomised crossover trial (two 14-day ad libitum UPF diets)
Population: Healthy young adults (mean BMI 23.4)
Country: Not stated in abstract
Period: Registered NCT06113146
Sample size: 41 completed
Inclusion and exclusion criteria: Healthy-weight adults

Exposure / intervention: UPF diet with slow eating-rate textures
Comparator: UPF diet with fast eating-rate textures, matched for palatability, energy served, energy density and variety
Endpoints: Daily energy intake; body weight; body composition
Statistical methods: Mixed models

Results: Energy intake 369 kcal/day lower on UPF Slow-ER vs UPF Fast-ER (221-517; P<0.001), consistent over 14 days and not explained by liking or macronutrients; no change in body weight; fat mass decreased 0.43 kg on Slow-ER.
Absolute risks: not reported
Authors' conclusion: Food texture-derived eating rate has a significant and sustained effect on energy intake from ultraprocessed diets.

CI internally consistent (stats/C-UPF-02_trials.py); effect size comparable to Hall 2019's UPF-vs-unprocessed difference.

Shows that within UPF diets, eating rate alone changes intake by about 370 kcal/day; implies that 'processing' per se is not the only driver.

Does not compare UPF with unprocessed food.

Applicable.

Mechanistic qualification of C-UPF-02: the overeating effect depends on food properties that vary within UPF.

Multidimensional assessment
Multidimensional assessment
Authenticity of the source	verified
Methodological quality	high
Risk of bias	low
Precision of results	moderate
Directness	indirect
Reproducibility	not replicated
Consistency with the overall evidence	consistent
Regional transferability	high
Adequacy of the interpretation (by the archive)	not applicable

Long-term weight effects.