Vegetarian diet is associated with a lower risk of chronic kidney disease in a population-based study.

Plant-based diets have received substantial attention in recent years, partly due to evidence linking high consumption of animal-based foods with adverse health outcomes. Moreover, plant-based diets are associated with both better cardiometabolic health and a lower environmental impact. The prevalence of chronic kidney disease (CKD) is increasing worldwide, yet evidence on the potential role of plant-based diets in this vulnerable patient population is limited. In particular, data on the role of habitual dietary patterns in CKD prevention remain scarce. Several studies using dietary indices, such as the healthy plant-based diet index, suggest that individuals with reduced kidney function may benefit from a healthy, balanced diet similar to that recommended for the general population. Initial evidence also indicates a lower incidence of CKD among those consuming diets rich in high-quality plant foods and low in animal products. However, these studies typically assessed diet using post hoc diet quality scores, and there is a lack of data examining habitual diet types in relation to CKD. While diet quality indices have consistently shown associations with CKD risk, they rely on investigator-defined scoring systems and may not fully capture real-world dietary behaviors. By contrast, habitual diet groups represent naturally occurring dietary patterns and may therefore provide complementary and more directly translatable evidence for clinical and public health recommendations. Therefore, the aim of this study was to assess the associations between habitual diet groups - high meat eaters, low meat eaters, poultry eaters, fish eaters, vegetarians and vegans - and incident CKD using data from the population-based UK Biobank study. Our hypothesis was that a habitual diet with a greater emphasis on plant-based foods would be associated with a lower incidence of CKD, consistent with their known cardiometabolic benefits in the general population. We used data from the UK Biobank, a large prospective cohort comprising over 500,000 participants aged 40–69 years at the time of recruitment. Baseline data collection was carried out between 2006 and 2010 at 22 assessment centres across Wales, Scotland and England. At baseline recruitment, participants completed a comprehensive touchscreen questionnaire that gathered information on socioeconomic status, lifestyle factors and health conditions. Dietary intake was assessed using a food frequency questionnaire (FFQ), capturing the consumption of 29 specific food items. In addition, biological material and physical measurements were collected by trained personnel. Further information on the study design, recruitment process, and baseline assessments has been documented elsewhere. The UK Biobank study received ethical approval from the National Health Service North West Multi-Centre Research Ethics Committee. The initial approval was granted in 2011 under the reference number 11/NW/0382. Subsequent renewals have occurred every five years, with approvals granted in 2016 (16/NW/0274) and 2021 (21/NW/0157). All participants provided written informed consent and all methods were performed in accordance with the relevant guidelines and regulations.