Diet, physical activity and behavioural disinhibition in middle-aged and older adults: a UK Biobank study

Background and aims Behavioural disinhibition is a prominent feature of multiple psychiatric disorders, and has been associated with poor long-term somatic health outcomes. Modifiable lifestyle factors including diet and moderate-to-vigorous physical activity (MVPA) may be associated with behavioural disinhibition, but their shared and unique contributions have not previously been quantified. Methods N=157,354 UK Biobank participants who completed the online mental health assessment were included (age 40-69, 2006-2010). Using principal component analyses, we extracted a single disinhibition score and four dietary component scores (prudent diet, elimination of wheat/dairy/eggs, meat consumption, full-cream dairy consumption). In addition, latent profile analysis assigned participants to one of five empirical dietary groups: moderate-healthy, unhealthy, restricted, meat-avoiding, low-fat dairy. Participants self-reported MVPA in minutes/week. Disinhibition was regressed on the four dietary components, the dietary grouping variable and MVPA. Results in men and women, behavioural disinhibition was negatively associated with prudent diet scores, and positively associated with wheat/dairy/eggs elimination. In men only, disinhibition was associated with consumption of meat and full-cream dairy products. Comparing groups, disinhibition was lower in the moderate-and-prudent diet (reference) group compared to all other groups. Absolute βs ranged from 0.02-0.13 indicating very weak effects. Disinhibition was not associated with MVPA. Conclusions Among middle-aged and older adults, behavioural disinhibition is associated with multiple features of diet. While the observational nature of UK Biobank does not allow causal inference, our findings foster specific hypotheses (e.g. early malnutrition, elevated immune-response, dietary restraint) to be tested in alternative study designs. ### Competing Interest Statement JH declares that he has in the past 3 years been a paid speaker for Medice, Biocodex, Shire, and Takeda, all unrelated to the work presented in the submitted manuscript. JB has been in the past 3 years a consultant to / member of advisory board of / and/or speaker for Takeda/Shire, Roche, Medice, Angelini, Janssen, and Servier. He is not an employee of any of these companies, and not a stock shareholder of any of these companies. He has no other financial or material support, including expert testimony, patents, royalties. HL has served as a speaker for Evolan Pharma and Shire/Takeda and has received research grants from Shire/Takeda; all outside the submitted work. The companies were in no way involved in the study design or analyses performed in the submitted manuscript, nor in the reporting of results or interpretation of findings. LJSS, DvR, HS, AA, LL, LGK and CAH declare that they have no affiliations with or involvement in any organization or entity with any financial interest or non-financial interest in the subject matter or materials discussed in this manuscript. ### Funding Statement This work was supported by the European Union Horizon 2020 Research and Innovation Program under grant agreement No 728018. The funding source has had no involvement in the study design, data collection, interpretation of the findings, or writing of this manuscript. ### 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: Access to the data was granted by UK Biobank following registration with their system and approval of our research project (project number 23668). The North West Multi-centre Research Ethics Committee oversees ethical approval of UK Biobank research procedures. See All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived. 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). Yes 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 UK Biobank data is available upon application