Political voting in the United Kingdom 2019 general election and risk of living with obesity in a nationally representative sample

Limited evidence from the United States suggests that county/state rates of people with obesity are positively associated with voting for the Republican Party presidential candidate, although this question has not yet been studied at the individual level, and/or outside of the United States, where the health and political systems are very different in other countries. Using individual level data, assess differences in rates of people with obesity according to political voting in the United Kingdom 2019 general election, and examine whether people living in constituencies won by Members of Parliament (MPs) from the Conservative Party were more likely to be living with obesity than those living in constituencies won by MPs from other parties. Data was obtained by the Ipsos KnowledgePanel where panellists are recruited via a random probability unclustered address-based sampling method. 4000/14,016 panellists were randomly invited to provide data on socio-demographics, health outcomes, voting behaviour and height/weight. 2668/4000 (67%) of invitees provided data, 95/2668 (3.5%) were not eligible to vote, with the remaining 2573 (96.5%) included. Conservative Party voters were more likely to be living with obesity than those who voted Labour (OR:1.42 95% CI (1.01–1.99)) or Liberal Democrats (1.54 95% CI (1.00–2.37)). Conservative Party voters on average had significantly higher BMI scores than those voting Labour and Liberal Democrats; BMI mean difference 0.88 points (95% CI: 0.16–1.61) between Conservative and Labour voters, and 1.04 points (95% CI: 0.07–2.02) between Conservatives and Liberal Democrats voters. There was no evidence participants living in constituencies won by Conservative MPs were more likely to be living with obesity than constituencies won by other party MPs. Governments and public health agencies may need to focus on the political affiliation of the public when developing strategies to reduce the number of people with obesity.