Veganism is becoming increasingly popular – not just in Ireland but on a global scale. The vegan diet offers many health benefits, but maintaining optimal health – that is, by receiving the right amount of nutrients – is often overlooked by those who follow a vegan lifestyle. The good news is that with a well-thought-out meal plan, you may well reap the benefits of a vegan diet.
More and more people have switched to a vegan diet. In the United Kingdom, according to recent studies, four per cent of the population are vegan. In 2021 a record-breaking 500,000 people worldwide signed up for Veganuary – a movement educating people about veganism by persuading them to try out a vegan lifestyle for the entire month of January. This growing interest in trying out a plant-based diet is also reflected in the growing range of vegan goods stocked on our supermarket shelves.
But what can you eat on a vegan diet? Which foods do you avoid and can you still receive those all-important nutrients? Are there any benefits of a vegan diet? Find out in our article.
What do you eat on a vegan diet?
You probably know what a vegetarian diet is: vegetarians mainly abstain from meat, fish and seafood. Pescatarians refrain from eating meat, but still eat fish – and flexitarians follow a primarily meat-free diet, but may occasionally eat meat and fish.
The vegan diet goes one step further. Vegans refrain from eating all animal products. This includes milk and other dairy products as well as eggs. In addition, they avoid industrially processed products that contain animal additives. These include, for example:
- gelatine (made from the connective tissue of cattle or pigs)
- animal colourant: true carmine/cochineal
- flavours from beef, game, pork or fish
Honey is also one of the products that vegans refrain from eating. The animal rights organisation PETA (People for the Ethical Treatment of Animals) clearly declares honey as a non-vegan product, since bees are also bred on a mass scale and are often killed in honey production. Overall, the vegan diet is referred to as an exclusively plant-based diet.
How can I tell which products are vegan?
Products that appear to be purely plant-based at first glance may contain hidden animal ingredients. This occurs, for example, in jams and confectionery, but also in juices and wines. They’re hidden products because they are only used during the manufacturing process, but are no longer found in the food itself. Therefore, they do not have to be included on the list of ingredients.
This can be gelatine in jam, for example, or added flavours and vitamins can be of animal origin, but they do not have to be declared in the list of ingredients.
For this reason, there are now some labels on the market that identify industrially processed products as vegan. Products with these labels are free of animal ingredients as well as hidden animal ingredient.
There are two common labels, each awarded by vegan organisations. One is the label used by the Vegan Society in the United Kingdom (left); the other is the vegan label used by the European Union (right):
Why is veganism becoming more popular?
There are many reasons why people become vegan. Often the decision to become vegan is linked to ethical reasons. People who live vegan, for example, are against factory farming and are committed to environmental protection and sustainability. For some, however, health benefits are also an argument.
How healthy is a vegan diet?
The question of whether a vegan diet is healthy or dangerous has been addressed by many nutritional societies. The German Nutrition Society (DGE) points out that a sufficient supply of certain nutrients is critical in a vegan diet – however, it does not generally reject a purely plant-based form of nutrition. However, the DGE does not recommend a vegan diet for pregnant women, breastfeeding mothers, infants or children and adolescents.
The US nutrition society, the Academy of Nutrition and Dietetics (AND) sees things differently. The American nutrition experts are of the opinion that the vegan diet can be healthy for all age groups and also during pregnancy and breastfeeding. They explicitly point out that the vegan diet must be well planned and should be accompanied by fortified foods and an additional intake of nutrient supplements. Many other nutrition societies, including the Australian, British and Canadian, also hold this view.
Benefits of a vegan diet
Current studies show that a vegan diet can have numerous positive effects on health. A purely plant-based diet boasts a higher intake of vitamins, minerals, antioxidants and fibre. In addition, the consumption of saturated fats and cholesterol is lower. Vegans often have a lower body weight and are at a lower risk of diet-related diseases, such as type 2 diabetes and cardiovascular diseases.
Of course, as a vegan you also have to pay attention to a healthy diet. The results of certain studies emphasise the importance of a varied plant-based diet with plenty of fresh fruit and vegetables and few industrially processed products.[4, 8]
What are the dangers of being vegan?
As explained in the previous section, the vegan diet can boost your overall health. However, as with any diet, it is important to plan your daily meals properly. You should therefore primarily use fresh products.
In supermarkets these days, you should have no problem finding vegan foods and substitute products – however, they may not be fresh. Such ready-made products are sometimes highly processed and can contain many additives as well as plenty of sugar, fat and salt.
To achieve a balanced vegan diet, you should pay extra attention to certain vitamins and nutrients. These are mainly vitamins and nutrients that are predominantly found in animal foods. If you do not ensure you receive these critical nutrients, you run the risk of developing nutrient deficiencies. A vegan diet can thus bring with it health disadvantages.
Which nutrients are important for a vegan diet?
One of the most frequently mentioned critical nutrients of a vegan diet is vitamin B12. The reason for this is that vitamin B12 is found in optimal quantities exclusively in animal foods and is an essential vitamin.
However, vitamin D, protein, calcium, long-chain omega-3 fatty acids, vitamin B2, iodine, zinc, selenium and iron are also among the potentially critical nutrients you must receive enough of with a purely plant-based diet.[101, 11]
Which vegan foods are good for nutrients?
You can cover the critical vitamins and nutrients with a well-planned plant-based diet. Let’s go through individual nutrients together now and determine when it makes sense to opt for nutrient supplements.
Can vegans get B12 naturally?
Vitamin B12 is the most critical nutrient in a vegan diet. You can hardly receive enough vitamin B12 through a purely plant-based diet. The form of the vitamin that is available to our bodies is produced by bacteria that are found in the digestive tract of animals, among other places. This is why vegans can develop a vitamin B12 deficiency over time.
Vitamin B12 in sauerkraut, mushrooms and algae
Experts believe that vitamin B12 can also be found in plant-based foods such as sauerkraut through bacterial fermentation. However, it is unclear whether our body can actually absorb the form of the vitamin contained in these foods. Moreover, the amounts of vitamin B12 found in these foods are very small.[12, 13]
Researchers suspect that there are sufficient amounts of vitamin B12 in algae products – for example, in spirulina, afa (Aphanizomemon flos-aquae) and chlorella, as well as in certain edible mushrooms, such as shiitake mushrooms. However, the content in these plant-based foods seems to vary greatly. These foods cannot therefore guarantee sufficient amounts of vitamin B12.[14, 15]
Food supplements with vitamin B12
Professional associations, such as the German Nutrition Society (DGE), but also the organisation PETA (People for the Ethical Treatment of Animals), generally advise vegans to take vitamin B12 supplements.
A daily intake of four microgrammes is recommended. To reach this amount, you can safely take food supplements with a vitamin B12 content of 1,000 microgrammes daily. Our body only actually absorbs a small part of the vitamin B12 supplement.
No maximum amount has yet been defined for vitamin B12. There is no evidence that an intake of up to 1,500 microgrammes has any negative effects on the body in studies.[16,17,18] According to various studies, supplementation with toothpaste containing vitamin B12 can also contribute to optimising your vitamin B12 levels.
Do vegans lack vitamin D?
Vitamin D is considered a critical nutrient for vegans. Only a few foods contain sufficient amounts of vitamin D – for example, salmon, mackerel and herring, as well as egg yolk and some edible mushrooms, such as mushrooms and chanterelles.
With enough exposure to sunlight, your skin can also produce vitamin D itself. So, give your skin regular sun exposure – that way, your body can supply you with sufficient amounts of vitamin D itself. However, this is easier said than done. How much vitamin D you can produce from the sun’s rays depends on the following factors, for example:
- where you live
- the time of year and day
- how often you can enjoy the sun daily
That is why it is recommended to take vitamin D supplements, especially during the darker months of the year.
According to the DGE, food supplements containing 1,500 to 2,000 IU (37 to 50 microgrammes) of vitamin D are advisable to ensure you cover your daily vitamin D requirement. If you have a vitamin D deficiency, higher doses may also be advisable.
However, if you already have optimal vitamin D levels and continue to take high-dose supplements, this can cause side effects, such as kidney stones and kidney calcification. That’s why it makes sense to check your vitamin D levels before you start taking supplements. One way to do this is with an at-home vitamin D test. For the test, you take a few drops of blood yourself at home before sending off your blood sample to be analysed in a specialised laboratory.
How do vegans get iodine?
Iodine is also a critical nutrient, not only for vegans. To prevent iodine deficiency, iodised table salt was introduced in Germany and other countries. If you season your daily meals with iodised table salt, this actively improves your iodine levels. Alternatively, you can also use sea salt mixed with seaweed. However, you should use salt sparingly to reduce the risk of high blood pressure. So, include other sources of iodine in your diet.
There are few plant-based foods containing iodine – algae products and supplements are one possibility. However, these often contain excessive amounts of iodine. Dried algae products with an iodine content of more than 20 milligrammes per kilogramme can be harmful to your health. Therefore, pay attention to information on the iodine content and the maximum recommended intake – do not use products whose packaging contains inadequate information or unclear instructions on use.
If you cannot integrate these iodine sources sufficiently into your diet, you can take iodine tablets after consulting a doctor. Pregnant and breastfeeding women should generally talk to their doctor about iodine supplements, as they need a higher dose of the nutrient.[4, 6, 22, 23]
Eating cabbage, soybeans and sweet potatoes can inhibit the absorption of iodine into your body. So, if your daily iodine intake is very low, you should eat less of these foods.
How do vegans get omega-3 fatty acids?
Your body needs omega-3 fatty acids, often referred to as healthy fats, to carry out various important functions. Among other things, omega 3 lowers blood pressure, dilates blood vessels and strengthens your immune system. These are the most important omega-3 fatty acids:
- Eicosapentaenoic acid (EPA)
- docosahexaenoic acid (DHA)
- alpha-linolenic acid (ALA)
If you eat a vegan diet, you will consume fewer semi-essential fatty acids, such as EPA and DHA, as these are mainly found in fish and fish oil. For a regular intake of EPA and DHA, however, you can take microalgae oil as a food supplement. In order to supply your body with the essential fatty acid alpha-linolenic acid, you can consume two to four tablespoons of certain vegetable oils daily. The fatty acid is found in rapeseed, linseed, walnut and hemp oil. Flaxseed, chia seeds and walnuts are another source of alpha-linolenic acid. [22,42]
Are vegans low in zinc?
You usually don’t need to turn to zinc supplements if you bring zinc-rich foods to your plate in a varied way. In order to prevent zinc deficiency, a vegan diet should include a good mix of plant-based zinc sources, such as whole grains, legumes, soy products, nuts and seeds. Yeast flakes are also rich in zinc and are popular in vegan cooking as a cheese alternative.
If you process foods in a certain way, you can boost your zinc levels even further. Roasting and fermenting will help you get the maximum zinc out of your meals. To improve your zinc absorption rate, you should also consume foods with plenty of vitamin C.
Tip: You can easily check your magnesium, selenium and zinc levels within the comfort of your own home with various mineral analysis kits.
What food is high in selenium?
Like zinc, you can also boost your selenium levels through a clever combination of different plant-based foods.
As a vegan, alternate your diet with mushrooms, asparagus, broccoli and white cabbage as well as onions or Brazil nuts. Pulses, which are an important part of the vegan diet, also contain selenium. In any case, pulses should ideally end up on your plate every day in a vegan diet because of their protein content.[6, 8]
How do vegans increase iron levels?
Even as a vegan, it is not that difficult to reach the recommended daily requirement of ten to fifteen milligrammes of iron, thereby preventing an iron deficiency. Great plant-based sources of iron mainly include legumes, wholemeal products, nuts, seeds and vegetables such as spinach or beetroot. Amaranth and quinoa, also boast a high iron content.
Pregnant and breastfeeding women need more iron. Therefore, it is especially important for them to increase their iron intake and, if necessary, to take iron supplements.[24, 25]
To improve the absorption of the iron found in plant-based foods, you should eat foods containing vitamin C, such as fruit, at the same time. Tea, coffee and milk, on the other hand, can inhibit iron absorption. Therefore, do not drink these beverages at the same time as consuming an iron-rich meal – instead, opt for a vitamin C-rich glass of orange juice.
Did you know that iron from plant sources has a lower bioavailability. What does this mean? Your body cannot use the iron as well as the iron from animal sources. You body can absorb the iron found in animal products up to 20 per cent, whereas plant-based iron has an absorption rate of up to five per cent.
What B vitamins should vegans take?
Reaching the optimal daily riboflavin (vitamin B2) levels of 1.0 to 1.4 milligrammes is possible on a vegan diet. Vitamin B2 is found primarily in oilseeds and nuts – for example, in flaxseeds and almonds, but also in legumes, whole grains and vegetables such as kale and broccoli. These foods also contain many of the other potentially critical nutrients needed for a vegan diet.[6,27,28]
Do vegans lack calcium?
Calcium is another nutrient that you can easily obtain from a purely plant-based diet. If you eat plenty of green vegetables such as broccoli, kale or rocket, as well as a variety of legumes, you can easily reach the recommended intake of 1,000 milligrammes per day.
Soy products, such as tofu, are also a good source of calcium. You can additionally purchase calcium-rich mineral water, which contains more than 150 milligrammes of calcium per litre.[6,29]
How do vegans get enough protein?
A sufficient supply of protein can be achieved well with plant-based foods. However, current studies do not yet show clearly enough whether purely plant-based products also provide you with enough indispensable amino acids. This is particularly important for infants and children, as they are still growing.
Did you know that a total of 20 different amino acids are needed to build up physical protein. These are called proteinogenic amino acids. Nine of these amino acids are indispensable, which means that our body cannot produce them itself, and we have to consume them through our diet. The quality of dietary proteins is measured by their bioavailability. The more of these nine amino acids you include in your meals, the better their bioavailability.
The DGE points out that the amino acids in animal and plant proteins are composed differently. Plant proteins do not always contain all amino acids, which is why their bioavailability is lower. There is a wide variety of plant-based protein sources that also bring other beneficial ingredients, such as abundant fibre. Particularly valuable plant protein sources include legumes, such as peas, beans and lentils, but also nuts, various seeds, cereal products and green vegetables.
You can receive the entire spectrum of amino acids through a targeted combination of plant protein sources: sensible meals include cereals with pulses – for example, lentils with rice. You can also do this by eating a variety of protein sources throughout the day.[30, 31, 32]
Your path to a healthy vegan diet
If you want to boost your health throughout veganism, you need to introduce a well-planned, varied diet into your everyday life. In addition, dietary supplements and nutrient-fortified foods will help you out.
The vegan food pyramid
The nutritionists Prof. Markus Keller, Stine Weder and Caroline Schaefer have developed the Giessen vegan food pyramid. This pyramid is handy for coming up with vegan meal plans and new tasty recipes.
The scientists used a 14-day vegan meal plan as a basis, which especially focuses on the critical nutrients. The vegan food pyramid presents the most important food groups and provides concrete food examples as well as quantity guidelines for a healthy and balanced vegan diet.
What does the vegan food pyramid consist of?
The basics of the Giessen vegan food pyramid hardly differ from the food pyramid of the DGE for people who eat all foods groups. Both pyramids recommend the same choice of drinks, the same amounts of fruit and vegetables and almost the same choice and amount of grains.
The vegan food pyramid consists of six levels. Each level represents one to three food categories. The lowest level represents the food category you should consume the most. The top level therefore corresponds to the food category you should consume the least.
Level 1: drinks
Drinks represent the lowest level of the vegan nutrition pyramid. Drink at least 1.5 litres per day, preferably calcium-rich water and non-alcoholic and low-calorie drinks.
Level 2: fruit and vegetables
The second level consists of vegetables and fruit. Aim for three portions of vegetables (at least 400 grammes) and two portions of fruit (at least 250 grammes) daily. In addition, you should eat seaweed daily – for example, a heaped teaspoon of nori flakes.
Level 3: whole-grain foods and potatoes
On the third level you’ll find wholemeal products and potatoes, of which you should consume three portions daily. For example, a portion in the morning could consist of about 80 grammes of porridge. At noon or in the evening, a portion of 200 to 250 grammes of cooked pasta or rice is ideal. Another portion could be two to three slices of wholemeal bread or about 150 grammes of wholemeal pasta.
Level 4: protein, milk substitutes, nuts and seeds
The fourth level of the vegan food pyramid consists of legumes and plant-based protein sources, dairy alternatives, and nuts and seeds.
Legumes are a particularly important source of many nutrients that are also found in meat and dairy products. That’s why it’s important to have a varied choice of pulses such as peas, lentils, chickpeas and beans, and protein-rich products such as tofu, seitan and lupine products.
Milk alternatives made from soy, oats or almonds, are now available in every supermarket. You can choose from a wide range of plant-based drinks, but you should go for the unsweetened varieties. Vegetable drinks are often enriched with calcium and thus contribute to your calcium supply.
Nuts and seeds are important sources of the critical nutrients iron, zinc and vitamin B2. Eat one to two portions (about 30 grammes in total) of different nuts and seeds daily – for example, a mix of almonds, cashews, walnuts, pumpkin and sunflower seeds.
Level 5: plant fats and oils
On the fifth level we have the vegetable fats and oils. Pay attention to the quality of the vegetable oils opt for variety here. Oils with particularly valuable nutrients include rapeseed, linseed and walnut oil. These oils contain the important omega-3 fatty acids. The Giessen vegan food pyramid also advises you to take one tablespoon of DHA-enriched flaxseed oil daily.
Level 6: snacks, sweets and alcohol
The final level contains salty snacks, sweets and alcohol. A guilty pleasure for many. However, vegan alternatives to these products are not beneficial to health. Therefore, even if you are vegan, you should avoid unhealthy snacks, sweets and alcohol as much as possible.
The Giessen vegan food pyramid also recommends that you take vitamin B12 supplements regularly and use iodised table salt or sea salt enriched with iodine-containing algae daily. Dietary supplements with vitamin D are recommended by experts between October and March.
Veganism & benefits of a vegan diet – at a glance
Which nutrients are important for a vegan diet?
The most critical nutrient in the vegan diet is vitamin B12. Other potentially critical nutrients in a purely plant-based diet are:
- Vitamin D
- Long-chain omega-3 fatty acids
- Vitamin B2
Should vegans take supplements?
You can receive many of the potentially critical nutrients on a purely plant-based diet. It is recommended that you regularly take vitamin B12 supplements for the long-term to fully reap all the benefits of a vegan diet. Take a supplement containing 1,000 microgrammes daily.
A vitamin D supplement is recommended for both vegans and non-vegans from October to March. To prevent vitamin D deficiency, make sure you take supplements with a vitamin D content of 1,500 to 2,000 international units (IU).
What is important for a vegan diet?
We recommend that you incorporate these recommendations into your daily diet.
- Eat five portions of vegetables and fruit.
- Combine whole grains with a variety of vegetables and pulses.
- Enjoy a wide range of legumes.
- Consume protein-rich plant foods, such as tofu, seitan and lupin products.
- Make meals extra crunchy and add nuts and oilseeds.
- Use iodised table salt or sea salt enriched with algae.
- Take a vitamin B12 supplement.
- Regularly check your nutrient levels.
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