Plant-based diets, both vegan and vegetarian, are rising in popularity in Australia. Between 2012 and 2016, the number of Australian adults whose diet is all or almost all vegetarian has risen from 1.7 million people (or 9.7% of the population) to almost 2.1 million (11.2%)1. The research also showed many Australians adopt a vegetarian diet for health and/or weight-loss reasons.
Vegetarian eating patterns are generally characterized by the exclusion of animal-based foods however there are various forms of vegetarian eating as listed below.
Table 1: Types of vegetarian eating patterns
|Type of Vegetarian Diet||What foods are usually consumed?|
|Vegan||Strictly plant foods only. No animal products of any nature. Often organic and ethically sourced options are preferred.|
|Lacto Vegetarian||Predominately plant based foods but also consume dairy products.|
|Lacto-Ovo Vegetarian||Predominately plant based foods but also consume eggs as well as dairy products.|
|Pesco Vegetarian||Predominately plant based foods but also consume fish and other seafood (may or may not consume eggs and dairy products) but avoid all other meats.|
|Semi Vegetarian||Predominately plant based foods with the occasional inclusion of fish, chicken and other meats.|
Scientific research suggests a number of possible health benefits to vegetarian eating with a 2016 systematic review and meta-analysis of 96 observational studies reporting significantly reduced body mass index, total-cholesterol, LDL-cholesterol and glucose levels in vegans and vegetarians compared with omnivores3. There was also a protective effect of vegan and vegetarian diets on incidence and/or mortality from ischemic heart disease and cancer3. It has also been suggested that vegetarian diets are an effective option for prevention of type 2 diabetes and could be used as a tool to improve blood glucose management4.
Well planned vegetarian eating pattern can meet nutritional needs for good health and may reduce the risk of cancer, cardiovascular disease, metabolic syndrome, insulin resistance, type 2 diabetes, hyperthyroidism, hypertension and obesity5-11. As well as experiencing overall better health, on average vegetarians also live longer than non-vegetarians12.
As they consist of predominantly plant based foods, most vegetarian eating patterns are lower in saturated fat and higher in dietary fibre, magnesium, potassium, folate, antioxidants such as vitamins C and E and phytochemicals compared to meat-containing diets13. However inadequately planned vegetarian diets may result in insufficient intakes of a number of key nutrients such as vitamin B12, iron, calcium and zinc in particular14. Furthermore, while the average energy content of vegetarian diets are similar to non-vegetarian diets, the bulkiness of a high intake of fibre-rich plant foods15 has the potential to result in lower energy and nutrient intakes in infants and young children with smaller appetites14,16. Table 2 outlines details of the possible nutrients at risk in a vegetarian eating pattern.
Table 2: Nutrient Intake in Vegetarian Populations
|Nutrient||Intakes in vegetarian populations||Amount in 1 serve of eggs||Benefits from eggs|
|Protein||Can be significantly lower than omnivore diets17,18. Possible lower intakes of the amino acids methionine and lysine19.||12.7g [25% DI]||Protein from eggs contain all essential amino acids. High quality and high digestibility19.|
|Long-Chain Essential Fatty Acids||Vegetarian and vegan diets tend to be high in omega-624,25 with little to no omega-3 DHA and EPA20,26.||114mg [71-127% AI]||Protein from eggs contain all essential amino acids. High quality and high digestibility19.|
|Vitamin B12||Low serum levels of vitamin B12 have been reported in adult and children vegan and vegetarians20,21.||0.8µg [40% RDI]||Eggs are one of the few food sources of vitamin B12 in an ovo-vegetarian diet.|
|Iron||Low iron levels can be common, particularly in young Australian vegetarian and semi-vegetarian women22. They have also been reported in some vegetarian children23.||1.7mg [14% RDI]||Eggs contain both heme and non-heme iron24|
|Calcium||Low in vegan dietary patterns2.||49mg [6% RDI]||While it is not common practice in Western populations, eggshells can be crushed and used as an extra source of calcium in the diet25.|
As the 2013 Australian Dietary Guidelines state, Australians following a vegetarian diet can still meet nutrient requirements if energy needs are met and the appropriate number and variety of serves from the five food groups are eaten throughout the day29. Choosing nutrient dense foods such as eggs and dairy (lacto-ovo vegetarians), nuts, seeds, legumes and green leafy vegetables is important to provide sufficient vitamins, minerals, essential amino acids and essential fatty acids.Amongst vegetarians, populations that are the most vulnerable to nutrient inadequacies include vegans26, children13, young women27 and pregnant women27,12,31,28. These groups, in particular, need to take extra care to ensure they are achieving a balanced, varied diet and taking a vitamin B12 supplement if advised by their health professional.
Eggs can play a significant role in a vegetarian diet due to the provision of high quality protein, vitamin B12, iron and omega-3s, nutrients that can be low in a vegetarian eating pattern. Overall, eggs are a highly nutritious food that can play an important role in the diets of ovo-vegetarians as well as pesco- and semi-vegetarians. Eggs are recommended as part of a healthy eating pattern that also includes adequate amounts of wholegrain breads and cereals, fruits, vegetables, legumes, low fat dairy foods and unsaturated fats.
This statement is for healthcare professionals only.
*One serve = 2x60g eggs (104g edible portion)
- Roy Morgan Research Polls. The slow but steady rise of vegetarianism in Australia. (2016).
- Clarys, P., et al. Comparison of nutritional quality of the vegan, vegetarian, semi-vegetarian, pesco-vegetarian and omnivorous diet. Nutrients 6, 1318-1332 (2014).
- Dinu, M., Abbate, R., Gensini, G.F., Casini, A. & Sofi, F. Vegetarian, vegan diets and multiple health outcomes: a systematic review with meta-analysis of observational studies. Crit Rev Food Sci Nutr, 0 (2016).
- Pawlak, R. Vegetarian Diets in the Prevention and Management of Diabetes and Its Complications. Diabetes Spectr 30, 82-88 (2017).
- Reid, M.A., Marsh, K.A., Zueuschner, C.L., Saunders, A.V. & Baines, S.K. Meeting the nutrient reference values on a vegetarian diet. MJA Open 1, 33-40 (2012).
- Huang, T., et al. Cardiovascular disease mortality and cancer incidence in vegetarians: a meta-analysis and systematic review. Ann Nutr Metab 60, 233-240 (2012).
- Orlich, M.J. & Fraser, G.E. Vegetarian diets in the Adventist Health Study 2: a review of initial published findings. Am J Clin Nutr [Epub ahead of print](2014).
- Yokoyama, Y., Barnard, N.D., Levin, S.M. & Watanabe, M. Vegetarian diets and glycemic control in diabetes: a systematic review and meta-analysis. Cardiovasc Diagn Ther 4, 373-382 (2014).
- Tonstad, S., Nathan, E., Oda, K. & Fraser, G.E. Prevalence of hyperthyroidism according to type of vegetarian diet. Public Health Nutr, 1-6 (2014).
- Orlich, M.J., et al. Vegetarian Dietary Patterns and the Risk of Colorectal Cancers. JAMA Intern Med 175, 767-776 (2015).
- Barnard, N.D., Levin, S.M. & Yokoyama, Y. A Systematic Review and Meta-Analysis of Changes in Body Weight in Clinical Trials of Vegetarian Diets. J Acad Nutr Diet (2015).
- Gray, N. Vegetarians have longer life expectancy than meat eaters, finds study. in Foodnavigator.com (2012).
- Position of the American Dietetic Association and Dietitians of Canada: Vegetarian diets. J Am Diet Assoc 103, 748-765 (2003).
- Messina, V. & Mangels, A.R. Considerations in planning vegan diets: children. J Am Diet Assoc 101, 661-669 (2001).
- Herrmann, W. & Geisel, J. Vegetarian lifestyle and monitoring of vitamin B-12 status. Clin Chim Acta 326, 47-59 (2002).
- Thomas, B. Manual of Dietetic Practice., (Blackwell Science Ltd., 2001).
- Alexander, D., Ball, M.J. & Mann, J. Nutrient intake and haematological status of vegetarians and age-sex matched omnivores. Eur J Clin Nutr 48, 538-546 (1994).
- Marsh, K.A., Munn, E.A. & Baines, S.K. Protein and vegetarian diets. MJA Open 1, 7-10 (2012).
- Millward, D.J. Macronutrient intakes as determinants of dietary protein and amino acid adequacy. J Nutr 134, 1588S-1596S (2004).
- Pawlak, R., Parrott, S.J., Raj, S., Cullum-Dugan, D. & Lucus, D. How prevalent is vitamin B(12) deficiency among vegetarians? Nutr Rev 71, 110-117 (2013).
- Schurmann, S., Kersting, M. & Alexy, U. Vegetarian diets in children: a systematic review. Eur J Nutr (2017).
- Baines, S., Powers, J. & Brown, W.J. How does the health and well-being of young Australian vegetarian and semi-vegetarian women compare with non-vegetarians? Public Health Nutr 10, 436-442 (2007).
- Pawlak, R. & Bell, K. Iron Status of Vegetarian Children: A Review of Literature. Ann Nutr Metab 70, 88-99 (2017).
- Makrides, M., Hawkes, J.S., Neumann, M.A. & Gibson, R.A. Nutritional effect of including egg yolk in the weaning diet of breast-fed and formula-fed infants: a randomized controlled trial. Am J Clin Nutr 75, 1084-1092 (2002).
- Brun, L.R., Lupo, M., Delorenzi, D.A., Di Loreto, V.E. & Rigalli, A. Chicken eggshell as suitable calcium source at home. Int J Food Sci Nutr 64, 740-743 (2013).
- Pawlak, R., Lester, S.E. & Babatunde, T. The prevalence of cobalamin deficiency among vegetarians assessed by serum vitamin B12: a review of literature. Eur J Clin Nutr 68, 541-548 (2014).
- Koebnick, C., et al. Long-term ovo-lacto vegetarian diet impairs vitamin B-12 status in pregnant women. J Nutr134, 3319-3326 (2004).
- Foster, M., Herulah, U., Prasad, A., Petocz, P. & Samman, S. Zinc Status of Vegetarians during Pregnancy: A Systematic Review of Observational Studies and Meta-Analysis of Zinc Intake. Nutrients 7, 4512 (2015).
- National Health and Medical Research Council. Australian Dietary Guidelines. (Commonwealth Department of Health and Ageing, Canberra, 2013).