Vegetarian diets are becoming increasingly popular in developed countries. While no reliable prevalence data for vegetarian populations exist, results of polls and surveys have reported population prevalence of between 1 and 10% in the European Union, the United States, and Canada (http://www.evana.org/index.php?id=70650). A recent study in the United States reported that 2.8% of respondents never ate meat, poultry, fish, or other seafood, although 4–10% would classify themselves as vegetarian (www.vrg.org/journal/vj2006issue4/vj2006issue4poll.htm). Vegetarian diets are often heterogeneous in nature, involving a wide range of dietary practices. These are summarized in Table 20.1. Even within classifications of dietary practices, there can be a high level of variability depending on the individual dietary restriction(s). Vegetarian or vegan diets may be practiced for a variety of reasons, including health, cultural, philosophical, religious, and ecological beliefs, or simply because of taste preferences. This chapter will discuss vegetarian and vegan diets and their impact on human health.
- Nutrient status
This is a preview of subscription content, access via your institution.
Tax calculation will be finalised at checkout
Purchases are for personal use onlyLearn about institutional subscriptions
European Vegetarian Union. How many veggies? http://www.evana.org/index.php?id=70650. Accessed 16 April 2016.
The Vegetarian Resource Group. How many adults are vegetarian? www.vrg.org/journal/vj2006issue4/vj2006issue4poll.htm. Accessed 20 April 2016.
Key TJ, Fraser GE, Thorogood M, Appleby PN, Beral V, Reeves G, et al. Mortality in vegetarians and non-vegetarians: detailed findings from a collaborative analysis of 5 prospective studies. Am J Clin Nutr. 1999;70(3 Suppl):516S–24S.
Kwok CS, Umar S, Myint PK, Mamas MA, Loke YK. Vegetarian diet, Seventh Day Adventists and risk of cardiovascular mortality: a systematic review and meta-analysis. Int J Cardiol. 2014;176:680–6.
Huang T. Cardiovascular disease mortality and cancer incidence in vegetarians: a meta-analysis and systematic review. Ann Nutr Metab. 2012;60:233–40.
Wang F, Zheng J, Yang B, Jiang J, Fu Y, Li D. Effects of vegetarian diets on blood lipids: a systematic review and meta-analysis of randomized controlled trials. J Am Heart Assoc. 2015;4:e002408.
Key TJ, Appleby PN, Rosell MS. Health effects of vegetarian and vegan diets. Proc Nutr Soc. 2006;65:35–41.
Yokamana Y, Nishimura K, Barnard ND, Takegami M, Watanabe M, Sekikawa A, et al. Vegetarian diets and blood pressure: a meta-analysis. JAMA Intern Med. 2014;174:577–87.
Appleby PN, Davey GK, Key TJ. Hypertension and blood pressure among meat eaters, fish eaters, vegetarians & vegans in EPIC-Oxford. Public Health Nutr. 2002;5:645–54.
Sacks FM, Appel LJ, Moore TJ, Obarzanek E, Vollmer WM, Svetkey LP, et al. A dietary approach to prevent hypertension: a review of the Dietary Approaches to Stop Hypertension (DASH) study. Clin Cardiol. 1999;22(7 Suppl):1106–10.
Rosell M, Appleby PN, Spencer EA, Key TJ. Weight gain over 5yr in 21,966 meat eating, fish eating, vegetarian and vegan men and women in EPIC-Oxford. Int J Obes (Lond). 2006;30:1389–96.
Sabate J. The contribution of vegetarian diets to human health. Forum Nutr. 2003;56:218–20.
Willet WC. Diet, nutrition and avoidable cancer. Environ Health Perspect 1995;103(8 Suppl):165–70.
World Cancer Research Fund/American Institute Cancer Research. Food, nutrition, physical activity and the prevention of cancer: a global perspective. Washington, DC: AICR; 2007.
Bouvard V, Loomis D, Guyton KZ, Grosse Y, Ghissassi FE, Benbrahim-Tallaa L, et al. Carcinogenicity of consumption of red and processed meat. Lancet Oncol. 2015;16:1599–600.
Dinu M, Abbate R, Gensini GF, Casini A, Sofia F. Vegetarian, vegan diets and multiple health outcomes: a systematic review with meta-analysis of observational studies. Crit Rev Food Sci Nutr 2016. [Epub ahead of print].
Yokoyama Y, Barnard ND, Levin SM, Watanabe M. Vegetarian diets and glycemic control in diabetes: a systematic review and meta-analysis. Cardiovasc Diagn Ther. 2014;4:373–82.
Tonstad S, Stewart K, Oda K, Batech M, Herring RP, Fraser GE. Vegetarian diets and incidence of diabetes in the Adventist Health Study-2. Nutr Metab Cardiovasc Dis. 2013;23:292–9.
Aune D, Ursin G, Veierod MB. Meat consumption and the risk of type 2 diabetes: a systematic review and meta-analysis of cohort studies. Diabetologia. 2009;52:2277–87.
Pan A, Sun Q, Bernstein AM, Schulze MB, Manson JE, Willett WC, et al. Red meat consumption and risk of type 2 diabetes: 3 cohorts of US adults and an updated meta-analysis. Am J Clin Nutr. 2011;94:1088–96.
Burckhardt P. The role of low acid load in vegetarian diet on bone health: a narrative review. Swiss Med Wkly. 2016;146:w14277.
American Dietetic Association & Dietitians of Canada. Position of the American Dietetic Association and Dietitians of Canada: vegetarian diets. J Am Diet Assoc. 2009;109:1266–82.
Mangels AR, Messina V. Considerations in planning vegan diets: infants. J Am Diet Assoc. 2001;101:670–7.
Messina V, Mangels AR. Considerations in planning vegan diets: children. J Am Diet Assoc. 2001;101:661–9.
Saunders TAB. Meat or wheat for the next millennium? A Debate Pro Veg. The Nutritional Adequacy of plant-based diets. Proc Nutr Soc. 1999;58:265–9.
American Dietetic Association & Dietitians of Canada. Position of the American Dietetic Association and Dietitians of Canada: vegetarian diets. J Am Diet Assoc. 2003;103:748–65.
Minnesota Nutrient Data Base 4.04, Tufts University School of Medicine, Boston. Revised 5/04.
Weaver CM, Proulx WR, Heaney R. Choices for achieving adequate dietary calcium with a vegetarian diet. Am J Clin Nutr. 1999;70(Suppl):543S–8S.
Hunt J. Bioavailability of iron, zinc and other trace minerals from vegetarian diets. Am J Clin Nutr. 2003;78(Suppl):633S–9S.
Foster M, Chu A, Petocz P, Samman S. Effect of vegetarian diets on zinc status: a systematic review and meta-analysis of studies in humans. J Sci Food Agric. 2013;93:2362–71.
Pawlak R, Lester SE, Babatunde T. The prevalence of cobalamin deficiency among vegetarians assessed by serum vitamin B12: a review of literature. Eur J Clin Nutr. 2014;68:541–8.
Stabler SP, Allen RH. Vitamin B12 deficiency as a worldwide problem. Annu Rev Nutr. 2004;24:299–326.
Craig WJ. Health effects of vegan diets. Am J Clin Nutr. 2009;89(Suppl):1627S–33S.
World Health Organisation/Food Agriculture Organisation (WHO/FAO). Fats and fatty acids in human nutrition. Report of an expert consultation. WHO: Geneva; 2008.
Suggested Further Reading
American Dietetic Association & Dietitians of Canada. Position of the American Dietetic Association and Dietitians of Canada: vegetarian diets. J Am Diet Assoc 2009;109:1266–1282.
McEvoy CT, Temple N, Woodside JV. Vegetarian diets, low-meat diets and health: a review. Public Health Nutr 2012;15:2287–2294.
The Vegetarian Society provides information on vegetarianism, vegetarian books and recipes, and links to related sites. www.vegsoc.org
Editors and Affiliations
© 2017 Springer International Publishing AG
About this chapter
Cite this chapter
McGirr, C., McEvoy, C.T., Woodside, J.V. (2017). Vegetarian and Vegan Diets: Weighing the Claims. In: Temple, N., Wilson, T., Bray, G. (eds) Nutrition Guide for Physicians and Related Healthcare Professionals. Nutrition and Health. Humana Press, Cham. https://doi.org/10.1007/978-3-319-49929-1_20
Publisher Name: Humana Press, Cham
Print ISBN: 978-3-319-49928-4
Online ISBN: 978-3-319-49929-1