Why do vegans avoid meat

Vegan diet - which nutritional supplements make sense?

What is meant by "vegan diet"?

While vegetarians consume products from live animals such as dairy products, eggs or honey, vegans avoid them. You only eat plant-based food. Additives and flavors, food supplements and medicines should also not be of animal origin. Some vegans also do without animal-derived materials for clothing and everyday items such as wool and leather.

How should a vegan diet be assessed?

In principle, any severe restriction in the choice of food increases the risk of not being optimally supplied with certain nutrients. In the long term, there can even be a shortage. Because the different food groups provide the body with different nutrients. Vegans therefore need a good knowledge of nutrition.

Plus points: With a cheap selection of foods with lots of vegetables, fruit, whole grain products, nuts and seeds, vegans are well supplied with potassium, magnesium, folic acid, vitamins C and E as well as fiber and health-promoting plant substances.

Risks: Compared to a traditional diet, vegans often eat less

The protein content of a vegan diet can also be too low if not enough protein sources such as pulses and nuts are used.

A study by the Federal Institute for Risk Assessment (BfR) showed that the B12 supply in vegans is good through the use of dietary supplements. A real problem child, on the other hand, is the iodine supply. This is already in need of improvement for people who eat mixed food, but this is even more pronounced for people who live vegan.

The same applies to bone health. This seems to be lower in people who live vegan. According to the current BfR, this is indicated by the combination of twelve biomarkers, which are usually present in lower concentrations in a vegan diet. Although further studies are necessary on this, you should still keep an eye on it here.

The German Nutrition Society (DGE) is of the opinion that a vegan diet during pregnancy and breastfeeding as well as in the entire Kindes- and adolescence is not suitable to adequately cover the nutritional requirements. The nutrition commission of the German Society for Child and Adolescent Medicine (DGKJ) is similarly critical. Anyone who would still like to eat vegan for themselves or their children in these special situations should be particularly well informed and possibly ask a nutritionist for advice. The attending specialists (pediatrician, gynecologist) should definitely know about the vegan diet.

According to a current recommendation by the Gesund im Leben networkPregnant women who eat vegan absolutely need suitable food supplements.

Special dietary supplement for vegans?

Special dietary supplements for vegans should provide the nutrients that can be neglected in a vegan diet. The products are not always put together sensibly:

  • Some products contain a random hodgepodge of vitamins, minerals and plant substances.
  • Some nutrients are unnecessary, such as vitamin C or folic acid, of which vegans usually get larger amounts through food, or they are contained in far too high doses.
  • A particular benefit has not been proven for substances such as borage oil or olive leaves.

What is actually useful?

Vitamin B12 is only contained in foods of animal origin and must be supplemented with food supplements (ideally so-called monoproducts that only contain vitamin B12) or fortified foods (e.g. breakfast cereals) in the case of a vegan diet; If the deficiency is proven, the doctor can also give an injection.

Attention: Vitamin B12 from plant sources such as sauerkraut, algae (for example spirulina), yeast, sea buckthorn or other plant-based foods is not vitamin-effective! These foods mostly contain substances similar to vitamin B12 (so-called analogs) that block the body's receptors for real vitamin B12.

You should pay particular attention to your iodine supply. The use of iodized salt in the household can help. Another possibility are seaweed products such as nori, whereby you have to watch out for possible overdoses. Talk to your doctor about the extent to which an additional supplement makes sense for you.

An undersupply of selenium and possibly also of zinc can occur, especially with a vegan diet.

Supplementation with vitamin D may also be advisable, but should be discussed with your doctor beforehand.

What should I look out for when using vegan supplements?

  • 4 micrograms of vitamin B12 per day are usually enough for adults to meet their needs.
  • Some vegan supplements contain more than a hundred times that amount. Taking such high doses of vitamin B12 does not make sense. Under physiological conditions, a maximum of 2 µg vitamin B12 (bound to intrinsic factor) is consumed per meal. In the case of high intake through supplements, 1-2% of the intake amount is additionally absorbed through passive intake, which does not result in any advantages for healthy people. On the contrary: more recent study results show that daily doses of> 55 µg may be associated with an increased risk of cancer.
  • If the doctor has found a vitamin B12 deficiency, you will be given appropriate medication or injections for therapy.
  • If you want to take an iodine supplement: The Federal Institute for Risk Assessment recommends that dietary supplements should not contain more than 100 µg or 150 µg per day for pregnant and breastfeeding women.
  • In the case of selenium, a daily amount of 45 µg in food supplements should not be exceeded.
  • Pay attention to the percentages for the daily dose of the NEM. For the individual nutrients, they should not be more than 100 percent. Many dietary supplements for vegans are combination products with a mixture of vitamin B12 and other vitamins and minerals that are used according to the "watering can principle". It is not uncommon for nutrient concentrations to far exceed the recommended intake levels. Both the benefits and risks of the combination products are unclear here.
  • Critically question ingredients that do not belong to the problematic nutrients for vegans (see above).

What else can I do?

For vegans, an annual check of the blood values ​​for critical nutrients, especially vitamin B12, makes sense. The iodine status can be measured via the excretion in the urine.

If you follow a vegan diet, you can get enough of the following critical nutrients with the help of a well-planned food selection:

Critical nutrientcontained in animal foodsvegan alternative
CalciumMilk, dairy productsVegetables (e.g. broccoli, kale, rocket), nuts (e.g. hazelnuts and Brazil nuts), legumes, meat substitutes made from soy, tofu, mineral water (calcium rich, i.e. more than 150 mg / L), foods fortified with calcium
Omega-3 fatty acidsfatty sea fishfoods fortified with microalgae oils
Vitamin B2Milk, dairy productsOil seeds (e.g. sunflower seeds, flax seeds, sesame seeds, pumpkin seeds), nuts, legumes, various types of vegetables (e.g. broccoli, kale), whole grains
ironMeat, meat productsOil seeds, nuts, legumes, various types of vegetables (e.g. broccoli, salsify), whole grain cereals; Vitamin C-rich juices or other foods improve iron absorption in the body
iodineSea fishSalt enriched with iodine, seaweed with moderate iodine content such as nori
Vitamin DHigh-fat animal foods such as herring, salmon or mackerel, as well as egg yolks, liver

Only small amounts are ingested through foods such as mushrooms, margarine and fortified orange juice. Bread with vitamin D yeast and UV-irradiated mushrooms, which contain significantly more vitamin D, are new to the market.

Vitamin D is mainly formed in the body when the skin is exposed to sunlight.
zincMeat (beef, poultry, pork), offal, some fish, shellfish, hard cheese and eggs

Oil seeds and nuts (especially cashews and pecans).

For an example calculation for a good zinc intake from plant-based foods, see DGE information (Table 1, Example 3).
seleniumMeat, fish (herring, mackerel), eggs, hard cheeseBrazil nuts (6 pieces), lentils, cabbage and onion vegetables, see information from the DGE


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Eat vegetarian or vegan: meat, no thanks

Vitamin B12 supplement for blood formation, nerve function and the immune system?

Iodine supply is falling again in Germany

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