Evidence map›Paper›PMID 42455834›Full record

ArticlePloS one2026

Association of mainly vegetarian and vegan diets with loneliness, social isolation and social withdrawal in a German population survey.

André Hajek, Razak M Gyasi, Supa Pengpid, Karl Peltzer, Karel Kostev, Pinar Soysal, Ashwin Kotwal, Lee Smith, Dong Keon Yon, Hans-Helmut König

Abstract read
In one paragraph

Article in PloS one, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

Who cites it

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No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

10 authors.

André HajekDepartment of Health Economics and Health Services Research, University Medical Center Hamburg-Eppendorf, Hamburg Center for Health Economics, Hamburg, Germany.ORCID https://orcid.org/0000-0002-6886-2745
Razak M GyasiAfrican Population and Health Research Center, Nairobi, Kenya.
Supa PengpidDepartment of Health Education and Behavioral Sciences, Faculty of Public Health, Mahidol University, Bangkok, Thailand.ORCID https://orcid.org/0000-0002-7714-8869
Karl PeltzerDepartment of Health Education and Behavioral Sciences, Faculty of Public Health, Mahidol University, Bangkok, Thailand.
Karel KostevUniversity Hospital Marburg, Philipps-University Marburg, Marburg, Germany.ORCID https://orcid.org/0000-0002-2124-7227
Pinar SoysalDepartment of Geriatric Medicine, Faculty of Medicine, Bezmialem Vakif University, Istanbul, Turkiye.ORCID https://orcid.org/0000-0002-6042-1718
Ashwin KotwalDivision of Geriatrics, Department of Medicine, University of California, San Francisco, California, United States of America.
Lee SmithCentre for Health, Performance and Wellbeing, Anglia Ruskin University, Cambridge, United Kingdom.
Dong Keon YonCenter for Digital Health, Medical Science Research Institute, Kyung Hee University College of Medicine, Seoul, South Korea.
Hans-Helmut KönigDepartment of Health Economics and Health Services Research, University Medical Center Hamburg-Eppendorf, Hamburg Center for Health Economics, Hamburg, Germany.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

aimThere is a very limited number of studies examining how diet is associated with social factors. The aim of this study was therefore to examine the association between type of diet and loneliness, social isolation and social withdrawal.

methodsCross-sectional data from the general adult population in Germany were used. The sample included 5,000 individuals aged 18-74 years. To quantify loneliness, the De Jong Gierveld tool was used. Social isolation was measured using the Lubben Social Network Scale and Bude/Lantermann tool. Social withdrawal was operationalized using the 25-item Hikikomori Questionnaire. Three types of diet were considered (mainly vegetarian; mainly vegan; neither vegetarian nor vegan, reflecting an omnivorous diet). The analysis was adjusted for sociodemographic, lifestyle-related, health-related and mental health-related covariates in multiple linear regressions.

resultsOverall, 15.4% of the individuals reported following a mainly vegetarian diet and 3.5% of the individuals surveyed followed a mainly vegan diet, with the remaining participants (81.1%) following an omnivorous diet. When adjusting for sociodemographic, lifestyle-related and health-related factors, individuals following a mainly vegetarian diet had significantly higher levels of perceived social isolation and social withdrawal compared to individuals following an omnivorous diet. However, these significant associations disappeared when adjusting for mental health-related covariates. Mainly vegan eaters feel more isolated and withdraw more from society compared to individuals following an omnivorous diet, even in the fully adjusted model.

conclusionFollowing a mainly vegan diet was associated with perceived social isolation and social withdrawal, even when adjusting for sociodemographic, lifestyle-related, health-related and mental health-related covariates. However, the variance explained by diet type was minimal (R2 close to zero and partial eta2 < 0.01), indicating limited practical relevance.

Indexed as

Diet, VeganDiet, VegetarianLonelinessSocial IsolationAdolescentAdultAgedCross-Sectional StudiesFemaleGermanyHumansMaleMiddle AgedSurveys and QuestionnairesYoung Adult

Identifiers

PMID42455834
PMCPMC13372175

What OpenQuestion holds

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LicenceCC BY
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.