Vegetarian Nutrition
Welcome to the Vegetarian Nutrition Projects
Lifestyle behaviors, including dietary patterns, play an important role in the prevention and management of cardiovascular disease risks, cardiovascular disease and other diseases. The Vegetarian Nutrition project consists of two separate reviews - Vegetarian Nutrition for Disease Management and Vegetarian Nutrition for Disease Prevention.
Disease Management (2024)
Vegetarian dietary patterns, including vegan diets, have been suggested as a healthy option to reduce dietary fats and cholesterol while providing cardiovascular health-promoting foods rich in dietary fiber, antioxidants, and phytochemicals. However, poorly planned vegetarian dietary patterns can limit intake of specific nutrients which can contribute to increased CVD risk. A vegetarian dietary pattern is one that does not include intake of flesh products such as meat, poultry or fish, and a vegan diet additionally does not include other animal products such as dairy products or eggs. Understanding the benefits and risks of vegetarian and vegan diets for adults with CVD risk factors, CVD and T2DM can help inform nutrition practitioners working with clients with these conditions who follow or are interested in following vegetarian or vegan diets.
A systematic review of randomized controlled trials (RCTs) was conducted to answer the research question: In adults with CVD risk factors (e.g., overweight/obesity, dyslipidemia, hypertension), CVD or T2DM, what are the effects of vegetarian diets on disease-specific outcomes of interest, including CVD risk factors, type 2 diabetes mellitus, and cardiovascular disease.
Key Findings:
- This systematic review included and analyzed 27 RCTs published from 1998 until May 2023 examining the effect of vegetarian diets in adults with CVD risk factors (n=17), CVD (n=3) and/or T2DM (n=7).
- In adults with cardiovascular risk factors, primarily overweight or obesity, vegetarian or vegan diets likely reduce BMI compared to therapeutic or non-therapeutic non-vegetarian diets.
- In adults with cardiovascular risk factors, vegetarian diets may be equal in efficacy to therapeutic non-vegetarian diets in reducing fasting blood glucose concentrations.
- In adults with T2DM, vegetarian and vegan diets likely reduce HbA1c and BMI compared to therapeutic or non-therapeutic non-vegetarian diets.
- In adults with T2DM, though evidence was mixed, it does suggest a benefit of vegetarian diets on diabetes medication needs compared to therapeutic or non-therapeutic non-vegetarian diets.
- In adults with CVD, vegetarian including vegan diets may have no effect on blood pressure, lipid profile, quality of life or cardiovascular events or mortality compared to therapeutic or non-therapeutic non-vegetarian diets.
Disease Prevention (2023)
Several observational studies have suggested that those following vegetarian, including vegan, dietary patterns may have a lower risk of certain diseases. A vegetarian dietary pattern is one that does not include intake of flesh products such as meat, poultry or fish, and a vegan diet additionally does not include other animal products such as dairy products or eggs. Understanding the benefits and harms of vegetarian and vegan diets for presumably healthy adults in the general population can help inform nutrition practitioners working with adult clients who follow or are interested in following vegetarian or vegan diets.
The EAL conducted an overview of systematic reviews, also called an umbrella review, to answer the research question: In presumably healthy adults in the general population, what are the relationships between vegetarian, including vegan, diets compared to non-vegetarian diets in health outcomes (incidence of cardiovascular disease, type 2 diabetes, cancer, bone fractures and cardiovascular events); nutrient status (concentrations of vitamin B12, calcium, hemoglobin, ferritin, iodine, vitamin D, omega-3s, BMI, bone density, muscle mass/lean body mass, fat mass); and other biomarkers (blood pressure and concentrations of LDL-cholesterol, triglycerides, and c-reactive protein).
Key findings:
- This umbrella review analyzed and summarized findings from 27 systematic reviews published from 2018 to January 2023. Evidence describing relationships between vegetarian diets and outcomes for adults in the general population was primarily observational.
- Moderate certainty of evidence describes vegetarian diets, including vegan diets, reduced cardiovascular disease incidence compared to non-vegetarian diets.
- Low and very low certainty of evidence described several other potential benefits of following a vegetarian and/or vegan diet, including reduced risk of cardiovascular disease mortality, reduced blood pressure, blood lipids, BMI and c-reactive protein concentrations.
- However, low and very low certainty evidence also described some potential harms of following vegetarian diets for adults in the general population, including lower bone mineral density, and increased risk of fractures and lower vitamin B12 and vitamin D concentrations for those following vegan diets.
Use the left navigation bar to view the results of the review. Expand the sections below titled Project Team and Disclosures for a listing of individuals who contributed their time and expertise to the development of this project, conflict of interest disclosures, and project funding information. Expand the section titled Resources/Articles for published articles from these reviews.
| Vegetarian Dietary Patterns for Adults: A Position Paper of the Academy of Nutrition and Dietetics, J Acad Nutr Diet 2025 Feb 7:S2212-2672(25)00042-5. (PDF) |
- Vegetarian Nutrition for Disease Prevention Project Team and Disclosures (2023)
- Resources/Articles
- Vegetarian Nutrition for Disease Management Project Team and Disclosures (2024)