Increasing numbers of people are choosing to be vegetarians – for health reasons, because of concern about climate change or animal welfare, or for religious reasons. But can they achieve an adequate diet and meet their nutritional needs?
Types of vegetarian
A vegetarian diet was traditionally a diet based on plant foods that excluded meat and animal products and fish, but different types of vegetarian diets are now common, including:
- Lacto-vegetarian: includes dairy foods, but no meat, fish, poultry and eggs.
- Ovo-lacto-vegetarian: includes dairy food and eggs, but no meat, fish or poultry.
- Ovo-vegetarian: includes eggs, but no meat, poultry, seafood or dairy products.
- Vegan: only plant foods are eaten.
- Pescetarian: includes fish and seafood, but no meat or poultry.
Benefits of a vegetarian diet
Plant foods are high in dietary fibre, provide vitamins, minerals and a range of beneficial compounds (including a wide range of antioxidants) and are low in saturated fat and sodium. For these reasons, people on vegetarian diets in Western countries tend to eat a diet closer to nutritional recommendations than many of their meat-eating counterparts.
There is also evidence that those who follow a well-balanced vegetarian diet have a lower incidence of some cancers, heart disease, high blood pressure, strokes, diabetes and obesity. This may be partly due to other healthy habits among those who choose vegetarian diets, however, studies show that this does not account for all the reduced risks of health problems.
Does a vegetarian diet provide adequate nutrition?
A well-planned vegetarian diet can meet nutritional needs for good health. However, vitamin B12 is found only in animal foods so a vegan diet will lack this vital vitamin B12 unless adequate amounts of foods fortified with vitamin B12 or a B12 supplement is taken. It can also be difficult for young children to eat the bulk of food needed to provide their high needs for some nutrients. Care is always needed when planning children’s diets, but especially for those given a vegetarian diet.
Potential dietary deficiencies
Fruits and vegetables are important in any diet, but on their own, they don’t provide all needed nutrients. A healthy vegetarian diet needs to also include a variety of plant foods such as legumes, nuts, seeds and wholegrains. The Australian Nutrient Reference Values have higher targets for zinc and iron in diets that exclude meat, poultry and seafood because these minerals may be less well absorbed from plant foods. Here are some of the nutrients that may need special attention in a vegetarian diet.
|Nutrients that vegetarians should pay attention to|
|Nutrient||Function in body||Vegetarian sources|
|Vitamin B12||Nerves, DNA. Red blood cells. Vitamin B12 deficiency is a serious health problem with irreversible symptoms if not treated early. All vegans and those not regularly consuming animal foods or foods with added vitamin B12 or an appropriate B12 supplement, are at high risk of vitamin B12 deficiency. Vegans and vegetarians should have their B12 status regularly assessed.||Found naturally only in animal products. Milk, cheese, yoghurt, eggs, vitamin B12 fortified foods (such as some soy products) and supplements.|
|Calcium||Strong teeth and bones.||Milk, yoghurt and cheese, green vegetables, almonds, tahini, calcium-enriched soy, oat, rice and nut beverages, canned sardines and salmon.|
|Zinc||Needed for muscle function, supports immune system and is involved in chemical reactions throughout the body.||Not as easily absorbed from plant sources as from animal foods National Reference Values are 50% greater for vegetarians than non-vegetarians. Milk, cheese, yoghurt, whole grains, soy, nuts, legumes, wheat germ, seeds|
|Omega-3 fats||Brain structure, membranes around cells and for heart health||Fish and other seafood, chia seeds, walnuts, flaxseeds (linseeds), canola|
|Protein||Healthy skin, muscles, body organs and bones||Eggs, milk, cheese, yoghurt, tofu and other soy products, nuts, lentils, legumes, seeds, wholegrains|
|Iron||Component of red blood cells, helps carry oxygen. Lack of iron can result in anaemia.||The non-haem iron found in plant foods and eggs is absorbed less well than the haem iron that makes up 40% of the iron in meat. The National Reference Values for iron suggest an intake 80% higher for vegetarians than for non-vegetarians. Wholegrain products, quinoa, legumes, vegetables, nuts, seeds. The vitamin C in fruits and vegetables improve absorption of non-haem iron so these foods should be included at each meal.|
|Iodine||Component of thyroid hormones.||Iodised salt (now mandatory in bread, except organic loaves), seaweed. Vegans may be at risk of iodine deficiency and all pregnant women should check with their doctor as to whether they should take a supplement of up to 150 mcg of iodine.|
|Vitamin D||Bone health and muscle function.||Sunlight, small amounts in some spreads/margarine, eggs, oily fish, vitamin D fortified soy milk and cereal, supplements|
Planning vegetarian meals
With careful planning a vegetarian diet can be varied and nutritious, just like an omnivorous diet. The internet is a great source of recipes and food ideas, as are vegetarian cookbooks and cooking classes. You can also seek help from an accredited practising dietitian or nutritionist who can advise you how to make sure your diet meets your needs.
Try to include these foods on a daily basis:
- Eggs, lentils, dried beans, nuts or seeds.
- Milk, cheese, yoghurt, or calcium-enriched soy, oat or rice beverages .
- Wholegrain breads and cereals.
- A wide variety of fruits (including avocado) and vegetables.
- Vitamin B12 fortified foods, if you don’t eat eggs, milk, cheese and yoghurt.
- Flaxseeds, chia seeds, walnuts, canola.
Last Reviewed: 09/08/2013
1. MJA Open. 2012; Vol 1: Issue 2: Is a vegetarian diet adequate? https://www.mja.com.au/open/2012/1/2 (accessed July 2013).
2. Nutrition Australia. Vegetarian diets. Last revised Nov 2011. http://www.nutritionaustralia.org/national/frequently-asked-questions/vegetarian-diets (accessed July 2013).
3. Dietitians Association of Australia. Vegetarian diets. http://daa.asn.au/for-the-public/smart-eating-for-you/nutrition-a-z/vegetarian-diets/ (accessed July 2013).
4. Mayo Clinic. Vegetarian diet: how to get the best nutrition. Updated July 2012. http://www.mayoclinic.com/health/vegetarian-diet/HQ01596 (accessed July 2013).
5. Australian Government Department of Health and Ageing. National Health and Medical Research Council. NZ Ministry of Health. Nutrient Reference Values for Australia and New Zealand Including Recommended Dietary Intakes. 2005. Iron: 187-189. Zinc: 235-240.
6. Australian Dietary Guidelines 2013, available at www.eatforhealth.gov.au (accessed July 2013)