Cardiovascular disease (CVD)

Evidence quality

Evidence quality: Moderate for cardiovascular risk factors and observational disease associations; lower for long-term clinical endpoints attributable specifically to vegan diets or plant-based meat alternatives (Koch et al., 2023; Satija et al., 2017; Crimarco et al., 2020). Randomized trials provide evidence for changes in LDL cholesterol and other intermediate outcomes, while most evidence on cardiovascular events comes from prospective cohorts that remain susceptible to confounding (Koch et al., 2023; Satija et al., 2017).

Lipids and dietary substitution

A 2023 meta-analysis of 30 randomized trials compared vegetarian or vegan diets with omnivorous diets (Koch et al., 2023). Plant-based groups had lower total cholesterol, LDL cholesterol, and apolipoprotein B, with an average LDL difference of -0.30 mmol/L; triglycerides did not differ significantly (Koch et al., 2023). A separate meta-analysis of 20 trials in 1,878 people with cardiovascular disease or elevated risk found a mean LDL reduction of 6.6 mg/dL after an average of six months and rated the LDL evidence as moderate certainty (Wang et al., 2023). These results support an effect on established risk markers but do not directly quantify a reduction in heart attacks or strokes (Koch et al., 2023; Wang et al., 2023).

The composition of the substitution helps explain why outcomes can differ (Päivärinta et al., 2020; Satija et al., 2017). In a 12-week randomized trial, replacing part of animal-derived protein with plant-derived protein increased fiber, lowered saturated-fat intake, improved fat quality, and lowered total and LDL cholesterol in the group with the largest plant-protein share (Päivärinta et al., 2020). The inherited claim that replacing animal products with plant foods often reduces saturated fat and increases fiber is therefore supported when the replacement foods have that nutrient profile; it is not guaranteed by a plant-based label alone (Päivärinta et al., 2020; Satija et al., 2017).

Blood pressure

A systematic review and meta-analysis of seven controlled trials found lower systolic and diastolic blood pressure with vegetarian diets than with omnivorous comparison diets, with mean differences of -4.8 and -2.2 mm Hg, respectively (Yokoyama et al., 2014). Results are not uniform across populations (Wang et al., 2023; Yokoyama et al., 2014). In the later meta-analysis limited to people with cardiovascular disease or elevated risk, the pooled systolic-pressure difference was -0.1 mm Hg and was not significant (Wang et al., 2023). The evidence therefore supports the statement that plant-forward diets can improve blood pressure in some settings, not that every vegan diet reliably lowers it (Wang et al., 2023; Yokoyama et al., 2014).

Plant-based meat alternatives

The SWAP-MEAT trial used a randomized crossover design in generally healthy adults who consumed at least two daily servings of plant-based alternative meat or corresponding animal meat for eight weeks per phase (Crimarco et al., 2020). LDL cholesterol was lower during the plant-alternative phase, and no adverse changes in the measured cardiovascular risk factors were identified (Crimarco et al., 2020). This is short-term risk-factor evidence; the study was not designed to determine whether plant-based meat alternatives reduce cardiovascular events over years of use (Crimarco et al., 2020).

Diet quality and processing

Plant-based is a broad descriptor rather than a nutrient-quality category (Satija et al., 2017). In three large U.S. cohorts, greater adherence to a plant-food pattern emphasizing whole grains, fruits, vegetables, nuts, and legumes was associated with lower coronary heart disease risk, whereas a pattern emphasizing refined grains, sweetened drinks, sweets, and similar less-healthy plant foods was associated with higher risk (Satija et al., 2017). These associations were observational and cannot by themselves establish causality (Satija et al., 2017).

Processing provides an additional distinction (Rauber et al., 2024). In 126,842 UK Biobank participants followed for a median of nine years, each 10-percentage-point increase in plant-sourced non-ultra-processed food contribution was associated with lower cardiovascular incidence and mortality, while plant-sourced ultra-processed food contribution was associated with higher incidence and mortality (Rauber et al., 2024). Residual confounding and dietary measurement error remain possible, but the results directly support the inherited limitation that ultra-processed plant foods can be associated with worse outcomes (Rauber et al., 2024).

The overall evidence supports plant-forward patterns as generally favorable for LDL cholesterol and potentially for blood pressure and cardiovascular risk, while showing that food choice, nutrient profile, and processing materially affect the association (Koch et al., 2023; Yokoyama et al., 2014; Satija et al., 2017; Rauber et al., 2024).