Vegetarian diets and risk of hospitalisation or death with diabetes in British adults: results from the EPIC-Oxford study

Abstract

Background: The global prevalence of diabetes is high and rapidly increasing. Some previous studies have found that vegetarians might have a lower risk of diabetes than non-vegetarians.

Objective: We examined the association between vegetarianism and risk of hospitalisation or death with diabetes in a large, prospective cohort study of British adults.

Methods: The analysed cohort included participants from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Oxford study who were diabetes free at recruitment (1993-2001), with available dietary intake data at baseline, and linked hospital admissions and death data for diabetes over follow-up (n = 45,314). Participants were categorised as regular meat eaters (≥50 g per day: n = 15,181); low meat eaters (<50 g of meat per day: n = 7615); fish eaters (ate no meat but consumed fish: n = 7092); and vegetarians (ate no meat or fish, including vegans: n = 15,426). We used multivariable Cox proportional hazards models to assess associations between diet group and risk of diabetes.

Results: Over a mean of 17.6 years of follow-up, 1224 incident cases of diabetes were recorded. Compared with regular meat eaters, the low meat eaters, fish eaters, and vegetarians were less likely to develop diabetes (hazard ratio (HR) = 0.63, 95% confidence interval (CI) 0.54-0.75; HR = 0.47, 95% CI 0.38-0.59; and HR = 0.63, 95% CI 0.54-0.74, respectively). These associations were substantially attenuated after adjusting for body mass index (BMI) (low meat eaters: HR = 0.78, 95% CI 0.66-0.92; fish eaters: HR = 0.64, 95% CI 0.51-0.80; and vegetarians: HR = 0.89, 95% CI 0.76-1.05).

Conclusions: Low meat and non-meat eaters had a lower risk of diabetes, in part because of a lower BMI.

Fig. 1. Associations between diet group and diabetes incidence in 45,314 EPIC-Oxford participants.

Regular meat eaters were defined as participants who consumed ≥50 g of meat per day and low meat eaters were defined as participants who consumed <50 g of meat per day. Model 1: Cox regression analysis stratified by sex, method of recruitment, region of residence, and adjusted for age, education, Townsend deprivation index, ethnicity, smoking, alcohol intake, and physical activity. P-heterogeneity represents significant heterogeneity in risk between diet groups based on Wald test statistics. EPIC European Prospective Investigation into Cancer and Nutrition

Fig. 2. Hazard ratios for diabetes in EPIC-Oxford men and women by body mass index and diet group.

Black squares indicate regular meat eaters, white squares low meat eaters, black circles fish eaters, and white circles vegetarians. Cox regression analysis stratified by sex, method of recruitment, region of residence, and adjusted for age, education, Townsend deprivation index, ethnicity, smoking, alcohol intake, and physical activity. Hazard ratios are relative to regular meat eaters with a body mass index reference level of 22.5–24.4 kg/m². CI confidence interval, EPIC European Prospective Investigation into Cancer and Nutrition