Meta-Analysis of Vegetarian or Vegan Diets and Blood Lipids

Quick Takes

  • This is an updated review and evaluation of 30 randomized controlled trials, with additional novel features of meta-analyses on apoB and comprehensive subgroup analyses.
  • Compared to omnivorous diets, vegetarian and vegan diets reduced blood levels of total cholesterol, LDL-C, and apoB.
  • Not only are plant-based diets environmentally favorable, they can potentially lessen the atherosclerotic burden from atherogenic lipids and lipoproteins and, therefore, reduce CVD risk.

Study Questions:

Does the consumption of plant-based vegetarian and vegan diets alter blood levels of total cholesterol, low-density lipoprotein cholesterol (LDL-C), triglycerides, and apolipoprotein B (apoB) compared to an omnivorous diet?


After a comprehensive search of relevant studies from 1980 to October 2022, 30 studies were ultimately selected and evaluated fitting these criteria: randomized controlled trials that quantified the effect of vegetarian or vegan diets versus an omnivorous diet on blood lipids and lipoprotein levels in adults aged >18 years. Lipid and lipoprotein blood concentrations at baseline and post-intervention were extracted from each study. Subgroup analyses that stratified outcomes of lipids by age, body mass index, continent, duration of trial, health status, intervention diet, intervention program, lipid-lowering therapy, outcome data analysis, sample size, and study design were performed.


Compared to the omnivorous diet group, the vegetarian or vegan diet group experienced reduced levels of total cholesterol (-0.34 mmol/L) and LDL-C (-0.3 mmol/L). A meta-analysis of apoB levels showed a 14% reduction (-12.92 mg/dL) in the plant-diet versus omnivorous diet group. No changes were observed in levels of triglyceride. The effect sizes were similar across age, continent, duration of study, health status, intervention diet, intervention program, and study design.


Consumption of vegetarian and vegan versus omnivorous diets reduces concentrations of total cholesterol, LDL-C, and apoB. This effect can potentially reduce atherogenic burden and, therefore, risk of cardiovascular disease (CVD).


This appears to be the first study to include as many as 30 randomized controlled trials using strict criteria and a large total sample size, and to evaluate changes in apoB levels with plant-based diets. Diet is a modifiable risk factor for atherosclerotic CVD (ASCVD), and this study demonstrates that plant-based diets can be key instruments decreasing risk across a variety of subgroups, in part through lipid-lowering properties. Adopting plant-based diets on a large scale can also potentially decrease population-wide ASCVD health and economic burden, and improve the environment through more sustainable forms of food production.

Clinical Topics: Cardiovascular Care Team, Diabetes and Cardiometabolic Disease, Dyslipidemia, Prevention, Hypertriglyceridemia, Lipid Metabolism, Nonstatins, Diet

Keywords: Apolipoproteins B, Atherosclerosis, Body Mass Index, Cholesterol, Cholesterol, LDL, Diet, Vegan, Diet, Vegetarian, Dyslipidemias, Hypertriglyceridemia, Lipids, Patient Care Team, Primary Prevention, Risk Factors, Triglycerides, Vegans, Vegetarians

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