Evoke Change

Global Studies Recommending Plant-Based Diets for Health

As global health bodies and governments continue to debate sustainable and cost-effective food systems, the scientific consensus on well-planned plant-based dietary patterns has solidified. This post serves as a definitive, curated resource for public health professionals, policymakers, and researchers.

Below is a curated set of landmark cohort studies, randomized clinical trials (RCTs), and umbrella/meta-analyses that consistently associate well-planned plant-based (and plant-forward) eating with better cardiometabolic outcomes, lower all-cause mortality, and reduced risk of several chronic diseases.

Summary Highlights: The Policy Message
Consistency Across Designs: Large prospective cohorts, randomized trials, and umbrella reviews converge on improved cardiovascular, diabetes, blood pressure, and weight outcomes with plant-based dietary patterns.
Quality Matters: Healthful plant-based diet indices (emphasizing whole grains, legumes, vegetables, fruit, nuts, and minimal ultra-processed foods) show the strongest risk reductions versus "unhealthful" plant diets.
Core Mechanisms: Benefits stem from lower saturated fat and dietary cholesterol, higher fiber and polyphenols, improved lipid profiles, enhanced insulin sensitivity, reduced inflammation, and gut-microbiome signatures supportive of metabolic health.
Policy Relevance: These robust findings sustain updates to national and global dietary guidelines, school and hospital food standards, chronic disease prevention strategies, and food labeling/marketing constraints.

Top 30 Studies and Reviews (Links)

(The list has been maintained, but key titles are bolded for quick scanning and the sections are visually separated.)

A. Cohort Studies (Population-Level Risk and Mortality)

EPIC‑Oxford: Plant‑based diets and long‑term health. Cambridge/Proceedings of the Nutrition Society (2021) https://www.cambridge.org/core/journals/proceedings-of-the-nutrition-society/article/plantbased-diets-and-longterm-health-findings-from-the-epicoxford-study/771ED5439481A68AD92BF40E8B1EF7E6
EPIC‑Oxford (BMJ 2019): Ischaemic heart disease and stroke in meat‑eaters, fish‑eaters, vegetarians, vegans https://www.bmj.com/content/366/bmj.l4897
Adventist Health Study‑2 (JAMA Intern Med 2013): Vegetarian dietary patterns and mortality https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/1710093
AHS‑2 (JAMA Intern Med 2015): Vegetarian diets and colorectal cancer risk https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2293088
Healthful vs unhealthful plant‑based diet and CHD risk (J Am Coll Cardiol 2017) https://www.jacc.org/doi/10.1016/j.jacc.2017.05.047
Plant‑based diet index and type 2 diabetes risk (JAMA Intern Med 2019) https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/2732799
Plant‑based diet quality and all‑cause mortality (Circulation 2019) https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.119.041014
Plant‑based diet indices and hypertension incidence (Hypertension 2020) https://www.ahajournals.org/doi/10.1161/HYPERTENSIONAHA.120.15144
Plant‑forward dietary patterns and heart failure risk (JACC HF 2019) https://www.jacc.org/doi/10.1016/j.jchf.2019.03.012
Plant‑based diet and CKD risk/mortality (CJASN 2019) https://journals.lww.com/cjasn/pages/articleviewer.aspx?year=2019&issue=02000&article=00014&type=Fulltext

B. Randomized Clinical Trials (Mechanisms and Disease Reversal)

Ornish Lifestyle Heart Trial (Lancet 1990): Lifestyle changes and CAD regression https://www.sciencedirect.com/science/article/abs/pii/S014067368091998X
Ornish 5‑year outcomes (JAMA 1998): Sustained CAD regression https://jamanetwork.com/journals/jama/article-abstract/187964
Esselstyn clinical series (Am J Cardiol 1999; Exp Clin Cardiol 2014): Plant‑based reversal/prevention of CAD https://www.sciencedirect.com/science/article/abs/pii/S0002914998008262 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4276041/
Portfolio Diet RCT (JAMA 2002): Cholesterol‑lowering foods comparable to statin effect https://jamanetwork.com/journals/jama/fullarticle/195214
Portfolio Diet LDL‑C reductions (Am J Clin Nutr 2011) https://academic.oup.com/ajcn/article/93/4/821/4597511
Low‑fat vegan diet in type 2 diabetes (Diabetes Care 2006) https://diabetesjournals.org/care/article/29/8/1777/24405
Low‑fat vegan vs ADA diet for T2D (Am J Clin Nutr 2009) https://academic.oup.com/ajcn/article/89/5/1588S/4596956
Workplace vegan intervention (GEICO study) – weight and lipid improvements (Eur J Clin Nutr 2015) https://www.nature.com/articles/ejcn2014149
Plant‑based diet and insulin resistance (Nutrients 2019) https://www.mdpi.com/2072-6643/11/10/2367
BROAD RCT (Nutr Diabetes 2017): Whole‑food plant‑based, ad libitum weight loss https://www.nature.com/articles/nutd201738

C. Meta‑analyses and Umbrella Reviews (Policy-Level Synthesis)

Umbrella review of vegetarian/vegan health outcomes (PLOS, 2024) PLOS article: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0292256
“Two decades of research show plant‑based diets are better for you” (overview of umbrella review) https://www.zmescience.com/science/news-science/two-decades-of-research-show-plant-based-diets-really-are-better-for-you/
Vegetarian diets and blood pressure (JAMA Intern Med 2014) – meta‑analysis https://jamanetwork.com/journals/jamainternalmedicine/fullarticle/1879722
Vegetarian diets and cardiometabolic risk (Crit Rev Food Sci Nutr 2017) – meta‑analysis https://www.tandfonline.com/doi/full/10.1080/10408398.2017.1394815
Plant‑based diets and lipid profile (Br J Nutr 2017) – meta‑analysis https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/effects-of-vegetarian-diets-on-blood-lipids-a-systematic-review-and-meta-analysis/8BFC1B641D6F8A8C0E5BEBB32A7B3E65
Plant‑based diets and inflammatory markers (Nutr Rev 2019) – meta‑analysis https://academic.oup.com/nutritionreviews/article/77/3/161/5238534
Plant‑based dietary patterns and depression risk (Mol Psychiatry 2018) – meta‑analysis https://www.nature.com/articles/s41380-018-0093-3
Plant‑based diet and cancer incidence (Int J Cancer 2019) – meta‑analysis https://onlinelibrary.wiley.com/doi/full/10.1002/ijc.32137
Whole‑food plant‑based diets and weight outcomes (Obes Rev 2020) – meta‑analysis https://onlinelibrary.wiley.com/doi/full/10.1111/obr.12997
DASH/Mediterranean plant‑forward patterns and CVD prevention (NEJM/PREDIMED 2013; pooled evidence anchoring plant‑forward policy) NEJM PREDIMED: https://www.nejm.org/doi/full/10.1056/NEJMoa1200303 DASH evidence base: https://www.nejm.org/doi/full/10.1056/NEJM199704173361601

Key Takeaways for Policy and Practice

The cumulative evidence from these 30 studies provides a strong mandate for proactive public health interventions:

Cardiovascular Health: Lower LDL-C, improved endothelial function, reduced angina, and even regression of atherosclerosis have been documented in intensive plant-based interventions. Cohort data confirms lower Coronary Heart Disease (CHD) incidence in those following healthful plant-based patterns.
Diabetes Prevention & Management: The evidence shows a reduced incidence of type 2 diabetes and consistently improved glycemic control in RCTs of low-fat plant-based diets, often achieved without energy restriction.
Metabolic Syndrome: Meta-analyses show lower blood pressure and clinically meaningful, sustained weight loss with whole-food plant-based patterns.
Cancer Risk: Cohorts show a lower risk of colorectal cancer, and umbrella reviews confirm generally lower cancer risk associated with these dietary patterns.

Call to Action

This resource is an essential tool for evidence-based change. We invite you to use it in your advocacy work.

What institutional or government policy do you believe needs updating first based on this overwhelming scientific evidence? Share your thoughts in the comments below.

A whole food plant-based diet has numerous benefits for both individuals and society. This type of diet is centred around consuming unprocessed and minimally processed plant foods, such as fruits, vegetables, whole grains, legumes, nuts, and seeds. This dietary pattern has been shown to reduce the risk of chronic diseases, improve health outcomes, and promote a more sustainable food system.

One of the most significant benefits of a whole food plant-based diet is its impact on chronic disease. Studies have shown that this type of diet can help reduce the risk of heart disease, type 2 diabetes, and certain types of cancer. For example, a large meta-analysis found that a plant-based diet was associated with a lower risk of heart disease and a lower risk of type 2 diabetes. This is likely due to the high intake of fibre, antioxidants, and phytochemicals in plant-based diets, which have been shown to have protective effects against chronic disease.

In addition to reducing the risk of chronic disease, a whole food plant-based diet can also improve health outcomes. This is because it is typically low in saturated fat and high in fibre, vitamins, and minerals. As a result, individuals following a plant-based diet are often at a lower risk of obesity, high blood pressure, and high cholesterol. They are also more likely to have improved gut health, better bone health, and a stronger immune system.

A whole food plant-based diet also has numerous benefits for the environment. This is because plant-based diets typically require fewer resources to produce, leading to lower greenhouse gas emissions, reduced land use, and less water consumption. Additionally, a shift towards a more plant-based diet could help to reduce deforestation, since a significant portion of deforestation is driven by the production of animal-based foods.

In conclusion, a whole food plant-based diet has numerous benefits for both individuals and society. It has been shown to reduce the risk of chronic disease, improve health outcomes, and promote a more sustainable food system. By consuming a diet centred around unprocessed and minimally processed plant foods, individuals can take an important step towards improving their health and the health of the planet

References

"Achievement of health improvement objectives through diet and lifestyle: A systematic review" - This study, published in the journal "Frontiers in Nutrition" in 2020, aimed to assess the impact of diet and lifestyle on various health outcomes, including heart disease, stroke, and type 2 diabetes. The authors conducted a comprehensive search of the literature and found that a diet rich in whole plant foods was associated with a lower risk of these chronic diseases. The authors concluded that promoting a diet centered around whole plant foods could help to improve public health.
"Plant-based diets and preservation of the natural world" - This article, published in the journal "BMC Medicine" in 2014, discussed the environmental benefits of a plant-based diet. The authors noted that plant-based diets require fewer resources to produce, leading to lower greenhouse gas emissions, reduced land use, and less water consumption. The authors also noted that a shift towards a more plant-based diet could help to reduce deforestation, since a significant portion of deforestation is driven by the production of animal-based foods.
"The health effects of vegan diets" - This review article, published in the journal "Annual Review of Nutrition" in 2009, summarized the evidence for the health benefits of a vegan diet. The authors conducted a comprehensive search of the literature and found that a vegan diet can be nutritionally adequate and associated with improved health outcomes, such as lower risk of heart disease, obesity, and type 2 diabetes. The authors concluded that a vegan diet can be a healthy option for individuals who choose to follow it