Surveys over the past 10 years have shown that Australians are increasingly consuming more plant-based vegetarian meals.
Many studies demonstrate the health benefits of vegetarian diets. As with any type of eating plan, vegetarian diets must be well planned to ensure nutritional needs are being met.
This clinical focus project shows that well planned vegetarian diets can meet almost all the nutritional needs of children and adults of all ages.
Sample single-day lacto-ovo-vegetarian meal plans were developed to comply with the nutrient reference values — including the increased requirements for iron and zinc at 180% and 150%, respectively, for vegetarians — for both sexes and all age groups set by Australia’s National Health and Medical Research Council and the New Zealand Ministry of Health.
With the exception of vitamin D, long-chain omega-3 fatty acids and extended iron requirements in pregnancy for vegetarians, the meal plans meet key requirements with respect to energy; protein; carbohydrate; total fat; saturated, poly- and monounsaturated fats; α-linolenic acid; fibre; iron; zinc; calcium; folate; and vitamins A, C, E and B12.
This article has been republished in the MJA
Although only 5%–6% of females and 1%–3% of males claim to be vegetarian,1,2 a 2010 Newspoll Survey (commissioned by Sanitarium Health and Wellbeing) found that seven out of 10 Australians are eating more plant-based meals than previously, in the belief that eating less meat and more plant foods improves overall health. As with any dietary practice, vegetarian diets need to be well planned to ensure that meals are healthy, delicious and nutritionally adequate.3
Research has shown that a well planned vegetarian diet can meet nutritional needs for good health4 and may reduce the risk of cancer,4-8 cardiovascular disease,5,8,9 metabolic syndrome, insulin resistance, type 2 diabetes,10-14 hypertension7,15,16 and obesity.11,17-19 Choosing plant-based meals is also environmentally beneficial.20-22 Vegetarian diets are generally lower in saturated fat and cholesterol and higher in dietary fibre, antioxidants and phytochemicals than non-vegetarian diets.4 It is likely that the combination of these factors provide vegetarians with a significant health advantage.7,23,24
Our article showcases well designed lacto-ovo-vegetarian meal plans for all age groups and both sexes that meet the nutrient reference value (NRV) requirements (Box 1), as well as the higher requirements set for iron and zinc for vegetarians.
Since the release, in 2006, of the revised Nutrient reference values for Australia and New Zealand including recommended dietary intakes,25 which supersede the 1991 recommended dietary intakes (RDIs),26 there has been some concern expressed about the ability to meet these recommendations. Compared with the 1991 RDIs, the 2006 NRVs recommend a small increase in iron for men, women and pregnant women and an increase in zinc for men (Box 2). For vegetarians, the further recommended increases in iron requirement (80% higher than current RDIs for non-vegetarians) and zinc requirement (50% higher than current RDIs for non-vegetarians) present additional challenges. The higher iron requirement is based on the assumption that only 10% of iron is absorbed from a vegetarian diet, compared with 18% from a mixed diet that includes meat.25,27 The higher zinc requirement is based on the fact that vegetarian diets have a higher phytate content25,28-30 and evidence that the phytate-to-zinc ratio can affect zinc absorption.25,27 Iron and zinc requirements are discussed in detail elsewhere in this supplement.31,32
The aim of our project was to develop single-day lacto-ovo-vegetarian meal plans that could be used as educational tools for vegetarian clients. Sample meal plans were developed for each sex and age category (Box 3), taking into account the appropriate physical activity level (PAL). The meal plans show the types and quantities of foods required to comply with the NRVs.
Foods were selected from a wide range of commonly available Australian foods. Each meal plan was devised to meet the recommended increased iron (180% of RDI) and zinc (150% of RDI) requirements within reasonable energy intakes while keeping macronutrient intakes within the acceptable macronutrient distribution range (AMDR).25 Other nutrients, such as α-linolenic acid (ALA), fibre, vitamin B12, vitamin C and calcium were included in amounts designed to meet the prescribed NRV value while not exceeding the upper level of intake (UL) for sodium or certain antioxidants such as vitamins A and E.25 When the NRVs differed between sexes within an age group, the meals were planned to meet the higher requirements within an energy range applicable to both males and females. In many cases, meal plans were sex specific. Infants less than 1 year old were not considered because of variable intake and reliance on breastmilk or infant formula as their main source of nutrition.
Energy requirements for each meal plan were determined according to the estimated energy requirements (EERs) outlined in the NRVs.25 Within each NRV age group under 18 years, the youngest child in the group was chosen, on the grounds that if nutritional requirements are met at a lower energy level, requirements will also be met for older or more active children. Additional energy may be added as required. For adults, average height (165 cm for women and 175 cm for men), along with PAL, determined the estimated energy requirements. Although the 1995 National Nutrition Survey states that the mean height for adults over 19 years is 161.4 cm for women and 174.9 cm for men,33 we adopted the average heights of 165 cm for women and 175 cm for men as used by the National Health and Medical Research Council in the recent revision of the Australian guide to healthy eating.34
A PAL of 1.8 (moderate activity) was chosen for teenagers and adults. A PAL equal to or above 1.75 is considered compatible with a healthy lifestyle for adults.25 A light PAL (1.6) was chosen for young children, older adults, pregnant women and lactating women. In line with NRV recommendations, an additional 1.4 MJ/day and 2.0 MJ/day were applied for pregnant and lactating women, respectively.25
As no vegetarian consumption data are currently available, food selection for meal plans was based on foods that are commonly available in Australia and are considered good sources of the nutrients in focus. Meal plans were initially created and analysed using FoodWorks Professional, version 5, 2007 software (Xyris Software, Brisbane, Australia) using the AUSNUT 1999 (Australian food and nutrient database, 1999 version) food composition database.35 As information on vitamins D, E and B12 content in foods was not available when meal plans were initially entered into FoodWorks, other sources were used to determine the content of these nutrients in our meal plans. The amounts of these nutrients in each meal plan were hand-calculated using the NUTTAB 2006 (nutrient tables for use in Australia, 2006 version) database.36 The RMIT Lipid Research Group’s fatty acid composition database37 was used to calculate ALA content.36 Food product nutrition information panels and nutrient information from company websites were used when needed.
Nutritional analyses were compared with the appropriate NRVs — RDI or adequate intake (AI).25 The use of RDI when planning diets for individuals ensures that the needs of most people are covered by these recommendations.25 When an RDI cannot be determined, an AI is used. The sodium content of each meal plan was compared with the daily recommended UL for sodium,25 and the saturated fat target was chosen to be less than 10% of total energy.25 For macronutrients, the goal was to achieve the AMDR. The AMDR is an estimate of the range of intake for each macronutrient for individuals (expressed as percentage contribution to energy) that would allow for an adequate intake of all other nutrients while maximising general health outcome.25
In planning vegetarian diets to ensure adequate nutritional intake, it is wise to be aware of some key nutrients.4 Iron, zinc, vitamin D and long-chain omega-3 polyunsaturated fatty acids (n-3 PUFAs) are considered nutrients of concern in vegetarian diets. It is important to note that vitamin D and long-chain n-3 PUFAs are also a concern for non-vegetarians who have limited sun exposure and consume minimal amounts of oily fish. Following, we highlight points of interest regarding these nutrients.
Cereal products are the main source of dietary iron for all Australians (a bigger contributor than meat, according to consumption data).33 Consequently, cereal products were also a significant source of iron in these meal plans. Cereals, legumes, nuts, seeds and fortified foods were selected mostly in combination with vitamin C-rich foods, as vitamin C enhances iron absorption.38 However, absorption concerns are less of an issue than previously thought.39 Even though iron requirements have been set higher for vegetarians, those with lower stores of iron or higher physiological need will absorb more iron and excrete less iron — an important adaptive mechanism.28,31,32
While red meat and seafood are good sources of zinc for non-vegetarians, other foods such as nuts, seeds, legumes and dairy foods are important sources of zinc for vegetarians and were included in the meal plans. Concerns about phytate as an inhibitor of zinc absorption are minimised by modern food processing methods.40 When considering zinc requirements, it is important to remember that the body can adapt to different levels of zinc intake by adjusting the amount of zinc absorbed relative to the amount of endogenous zinc lost.41,42
Given that vegetarian diets exclude fish as a source of n-3 PUFAs, it is important to include adequate amounts of short-chain n-3 PUFAs such as ALA (found predom-inantly in chia seeds, flaxseeds and walnuts). Small amounts of these seeds were included in the meal plans and provided significant amounts of ALA. ALA is endogenously converted to long-chain omega-3 fatty acids, but conversion depends on age, sex and dietary composition.43 The meal plans used minimal amounts of omega-6 fatty acids (oils and margarines) to optimise conversion.43
Vitamin D deficiency is not just a concern for vegetarians.44 The average dietary intake of vitamin D for Australians is 2–3 μg/day, which is substantially below the AI of 5 μg/day (for children and younger adults).25 Important dietary sources of vitamin D are margarine, eggs, vitamin D-fortified soy milk, and oily fish.45 Minimal amounts of margarine and eggs wer e included in the meal plans, due to a focus on whole plant-food sources of fat, such as nuts, seeds and avocado. Vitamin D-fortified soy milk was not included in the meal plans, as its availability is currently limited in Australia. The AI for vitamin D assumes most Australians receive some vitamin D from the sun to adequately meet requirements.25,45 Those with limited sun exposure, older adults (with higher requirements) or those with dark skin should supplement their diet with vitamin D.4,45
The 13 sample meal plans are available online at http://www.sanitarium.com.au/~/media/sanitarium/sns-pdfs/meal-plan-summary-tables.ashx. The full nutritional analyses for all sample meal plans are available at http://www.sanitarium.com.au/~/media/sanitarium/sns-pdfs/meal-plans-and-analyses.ashx. Almost all meal plans met key NRVs (for energy; protein; carbohydrate; total fat; saturated, poly- and mono-unsaturated fats; ALA; fibre; iron; zinc; calcium; folate; and vitamins A, C, E and B12), including the increased requirements for iron and zinc. An exception was for pregnant women, for whom increased iron requirements were not met. AI levels for vitamin D and long-chain n-3 PUFAs were not met across all meal plans. Below is a brief explanation of the analysis. Four examples of single-day vegetarian meal plans are presented in Box 4, and a nutrient analysis of each plan is provided in Box 5.
The NRV goals for energy were met based on the youngest child in each NRV category and on average heights for adults, with a PAL of 1.8 for adults and 1.6 for younger children, older adults, pregnant women and lactating women.
Protein, carbohydrate and fat intakes were within the AMDR. The proportion of total energy contributed by saturated fat was consistently below the 10% target. Polyunsaturated and monounsaturated fats were the predominant sources of fat in each of the sample meal plans.
The AI was exceeded in all meal plans. There is no UL set for fibre, as a high intake of dietary fibre does not result in adverse effects when consumed as part of a healthy diet.25
The increased iron requirement for vegetarians (180% of RDI) was achieved for all meal plans with the exception of the meal plan for pregnant women. The best vegetarian sources of iron in our meal plans were firm tofu, iron-fortified breads and breakfast cereals, cashews, chickpeas, pumpkin seeds, sesame seeds, brown rice, fortified malted chocolate powder and tabouli.
The increased zinc requirement for vegetarians (150% of RDI) was achieved for all meal plans, including adult males with the highest zinc requirements, without exceeding energy and fat needs. The best vegetarian sources of zinc in our meal plans included muesli, pumpkin seeds, sunflower seeds, wheatgerm, tofu, brown rice and sundried tomatoes.
As the vitamin B12 content of each meal plan was hand-calculated, the values are approximate. All meal plans, including those for lactating women, meet the RDI for vitamin B12. In our meal plans, the best sources of vitamin B12 were milk, fortified soy milk, yoghurt, cheese, egg and fortified yeast spread.
Calcium requirements were easily met for all meal plans, including those for adolescents and older adults, who have the highest requirements. Care was taken not to exceed the UL for calcium (2500 mg) in high-energy meal plans. The best vegetarian sources of calcium in our meal plans were low-fat milk and cheese, tofu (calcium set), fortified soy milk, yoghurt, sesame seeds and sesame paste (tahini).
As the vitamin E content of each meal plan was hand-calculated, the values are approximate. All meal plans met vitamin E requirements. The best sources of vitamin E in our meal plans were tahini, sesame seeds, wheatgerm, almonds, peanut butter, olive oil, margarine and eggs.
As the vitamin D content of each meal plan was hand-calculated, the values are approximate. The meal plans did not meet the AI for vitamin D. The small amount of vitamin D accounted for in the analyses was attributed to margarine and cheese. Some brands of soy milk are fortified with vitamin D and provide a good source for vegetarians. Our analysis did not take into account vitamin D derived from safe sun exposure.
Vegetarian diets cannot meet the requirements for n-3 PUFAs unless vegetarian docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) supplements (derived from microalgae) or fortified foods are consumed. As DHA/EPA-fortified foods are not widely available in Australia, long-chain n-3 PUFAs were not analysed in our meal plans. Although there is no separate official recommendation for n-3 PUFAs for vegetarians, it is suggested that they double the current AI of ALA if they do not consume a direct source of DHA and EPA, as ALA is converted to DHA and EPA.43 People with increased need for n-3 PUFAs (eg, pregnant women, older people and people with diabetes) may benefit from adding a microalgae-derived DHA and EPA supplement.46
Requirements for folate, vitamin C and vitamin A were met for all meal plans. Salt was not added to the meal plans, but the sodium content of the meal plans would be lower if the food composition database contained more food options without added sodium. Sodium levels did not exceed the UL.
Our meal plans were designed to be nutrient-dense in order to meet nutritional requirements without supplying excess energy. For people who have higher energy needs, additional discretionary kilojoules may be added. A vegetarian dietary pattern that focuses on nutrient density rather than energy deficit will naturally assist with weight loss and maintain healthy weight status in the long term.47-49
The higher iron requirement (180% of RDI) recommended for pregnant vegetarian women translates to 49 mg per day. Of interest, the UL during pregnancy is 45 mg.25 Our meal plan was only able to provide 36.6 mg within a reasonable energy intake. However, it is well recognised that the increased iron requirements during pregnancy can be difficult to meet, even for non-vegetarian women, and iron supplements are commonly recommended.4 The iron content of most multivitamin supplements formulated for pregnant women would easily compensate for this shortfall.
In our dietary analysis, fibre intakes were well above the RDIs and suggested dietary targets. There is currently no UL set for dietary fibre and there are no significant adverse effects of a high fibre intake eaten as part of a healthy diet.25
While we attempted to use mostly whole plant foods, in order to meet the NRVs (including the higher requirements for iron and zinc), some commonly available fortified foods were included (eg, soy beverages fortified with calcium and vitamin B12; iron-fortified cereals and bread; fortified malted milk powder; and fortified yeast spread). The analyses were also limited to values available in the AUSNUT database used by FoodWorks in our analyses. There are also limitations in using the NRVs for estimating dietary adequacy. RDIs overestimate needs (as they are designed to meet the needs of the majority of the population) and don’t take into account adaptive responses, as with iron31 and zinc32 or the protective phytonutrients from plant foods. These issues are particularly relevant to vegetarians.
Requirements for most key nutrients (except vitamin D, long-chain n-3 PUFAs and iron during pregnancy) can be met across the life cycle by well planned plant-based lacto-ovo-vegetarian diets. Furthermore, nutrient-dense vegetarian diets are more likely to provide additional health benefits, particularly with respect to prevention and treatment of many chronic diseases.
1 Definitions of nutrient reference values25
3 Nutrient reference value (NRV) categories by age and sex, showing appropriate physical activity level (PAL) as a rationale for developing sample meal plans
4 Four sample vegetarian meal plans*
2 fortified wholegrain wheat biscuits with 1/2 cup low-fat fortified soy milk with 1 banana and sprinkle (< 10 g) of chia seeds; 1 slice iron-fortified toast with Marmite and margarine; 1/2 cup freshly squeezed orange juice
5 Nutrient analyses for the four sample vegetarian meal plans presented in Box 4
ALA = a-linolenic acid. CHO = carbohydrate. LC n-3 PUFA = long-chain omega-3 polyunsaturated fatty acids. MUFA = monounsaturated fatty acids. NRV = nutrient reference value. PUFA = polyunsaturated fatty acids. RDI = recommended dietary intake. SFA = saturated fatty acids. UL = upper level of intake. y = years. * NRVs for Australia and New Zealand (RDI and adequate intake).25 † Energy value range is applicable to both male and female for the youngest in this NRV age group (males being the higher and females being the lower value). If additional energy is required in an individual diet for an older child, add discretional kJ from foods including avocado, dried fruit, fresh juice, peanut butter and olive oil spread. Nutritional requirements are still met. ‡ The energy in this meal plan meets the requirements for a lower PAL of 1.6 (light activity), associated with an estimated energy requirement of 8900–9200 kJ. If additional energy is required in an individual diet, add discretionary kJ. Nutritional requirements are still met. § Energy range is provided to be applicable to the large age range in this NRV group. If additional energy is required, add discretionary kJ. Nutritional requirements are still met. ¶ Acceptable macronutrient distribution range.25 ** This sample meal plan did not meet the extended RDI for iron (providing 180% of RDI for iron during pregnancy results in a level that is above the UL).