Plasma lipids and glycaemic indices in australians following plant-based diets versus a meat-eating diet

Background: Vegan and vegetarian dietary patterns are known to beneficially modulate risk factors for cardiovascular disease; however, the current literature does not differentiate between various plant-based diets. This study aimed to examine the association between various plant-based diets and plasma lipids and glycaemic indices compared to a regular meat-eating diet.

Methods: A cross-sectional study of Australian adults (n = 230) aged 30-75yrs habitually consuming the following were recruited: vegan, lacto-vegetarian, pesco-vegetarian, semi-vegetarian, or regular meat-eater. Multivariable regression analysis was used to adjust for covariates.

Results: Compared to regular meat-eaters, vegans had significantly lower total cholesterol (-0.77mmol/L,95% CI -1.15, -0.39, P < 0.001), low-density lipoprotein cholesterol (LDL-C, -0.71mmol/L, 95% CI -1.05, -0.38, P < 0.001), non-high-density lipoprotein cholesterol (non-HDL-C, -0.75mmol/L, 95% CI -1.11, -0.39, P < 0.001), total cholesterol/HDL-C-ratio (-0.49mmol/L, 95% CI -0.87, -0.11, P = 0.012), fasting blood glucose (FBG, -0.29mmol/L, 95% CI -0.53, -0.06, P = 0.014), haemoglobin A1C (-1.85mmol/mol, 95% CI -3.00, -0.71, P = 0.002) and insulin (-1.76mU/L, 95% CI -3.26, -0.26, P = 0.021) concentrations. Semi-vegetarians had significantly lower LDL-C (-0.41mmol/L, 95% CI -0.74, -0.08, P = 0.041) and non-HDL-C (-0.40mmol/L, 95% CI -0.76, -0.05, P = 0.026) and lacto-ovo vegetarians had significantly lower FBG (-0.34mmol/L, 95% CI -0.56, -0.11, P = 0.003) compared to regular meat-eaters. There were no differences in HDL-C and triglycerides between plant-based and regular-meat diets.

Conclusions: Plasma lipaemic and glycaemic measures as a collective were more favourable among vegans, whereas among lacto-ovo vegetarians and semi-vegetarians, only some measures were favourable.

Trial registration: ACTRN12621000743864. Date 6/11/2021.