Abstract
Adopting plant-based diets high in fiber may reduce global warming and obesity prevalence. Physiological and psychological determinants of plant-based food intake remain unclear. As fiber has been linked with improved gut-brain signaling, we hypothesized that a single plant-based (vegetarian and vegan) compared to an animal-based (animal flesh) meal, would induce higher satiety, higher mood and less stress. In three large-scale smartphone-based studies, adults (nall = 16,379) ranked satiety and mood before and after meal intake. Meal intake induced satiety and higher mood. Plant-based meal choice did not explain differences in post-meal hunger. Individuals choosing a plant-based meal reported slightly higher mood before and smaller mood increases after the meal compared to those choosing animal-based meals. Protein content marginally mediated post-meal satiety, while gender and taste ratings had a strong effect on satiety and mood in general. We could not detect profound effects of plant-based vs. animal-based meals on satiety and mood.
- plant-based
- animal-based
- single-meal
- hunger
- satiety
- mood
- planetary health diet
- smartphone-based
- online study
Competing Interest Statement
The authors declare no competing interests. Authors had the following dietary adherences at the time of study: omnivorous (LdB, AV), vegetarian (AVW), vegan (EM, MZ).
Funding Statement
Funding was provided by the Max Planck Society and a promotion stipend by the German Federal Environmental Foundation (EM).
Author Declarations
I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.
Yes
The details of the IRB/oversight body that provided approval or exemption for the research described are given below:
The Ethics Committee of the Medical Faculty of the University of Leipzig approved the study protocol and all participants provided written informed consent. The study was divided into three sub-studies and pre-registered at https://osf.io/a7yts (28 Nov 2019).
I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.
Yes
I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).
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I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable.
Yes
Footnotes
Gender-sensitive language was used throughout; Figures 1 + 2 revised; Supplemental files updated; Table 2; all updated according to reviewer revision requests.
Data Availability
Raw data, scripts and meal photos are stored at https://osf.io/mqc5d/ and can be used for further nutrient analysis or other purposes upon request to the corresponding author.