The vegan diet is popular but not automatically healthy

A vegetarian or vegan diet is said to be especially popular among girls and young women. But despite what some people think, these diets, especially vegan diets, aren’t automatically healthy. A vegan diet can lead to nutritional deficits due to the limited choice of foods. These deficits can cause clinically relevant symptoms if not compensated. One of the things to keep in mind is the need for sufficient amounts of vitamins B12 and B6, as well as Vitamin Dsays nutritionist Bettina Dörr, PhD, from Munich, who specializes in applying nutritional science to everyday practice.

Vegetarian and vegan diets

According to Dörr, vegetarian diets can be categorized into the following main types:

  • Ovo-lacto vegetarian (excluding meat and fish)

  • Ovo vegetarian (excludes meat, fish and dairy products)

  • Lacto vegetarian (excludes meat, fish and eggs)

  • Vegan (excludes meat, fish, eggs, dairy products and honey)

  • Raw vegan (excludes meat, fish, eggs, dairy, honey and heated foods)

Here are some additional groups:

  • Fruitarians only want to eat plant products that do not harm the plant itself (apples and nuts, for example, but not carrots or potatoes).

  • Pescatarians exclude meat but always eat fish or seafood.

  • Dirty vegetarians avoid meat and fish but, according to Dörr, they don’t pay particular attention to their diet and eat a lot of ready-made products and confectionery.

  • Flexitarians appreciate a balanced diet and eat meat or fish in moderation, but not particularly often.

Another diet is the orthorexic diet. Followers of this diet force themselves to have a healthy diet and are afraid of getting sick from unhealthy foods. As the nutrition scientist explains, people with orthorexes establish their own definitions of what is healthy. While some abstain from certain foods (eg, household sugar), others eliminate entire food groups and eat only raw foods. Compulsive behavior can show up in specific methods of preparing food or adhering to set mealtimes.

The overwhelming majority of orthorexic people are young women. As a study from the University of Göttingen shows, orthorexic behavior is most evident in active women who play sports, especially top athletes. Children can also be affected by orthorexia if their parents are.

Critical nutrients

By following a vegan diet, it’s possible to ingest enough essential nutrients, even with plant-based foods, according to Dörr. The prerequisite for this is a good knowledge of foods and nutrients. However, more and more food is being “simply left out”, without considering the consequences. This factor should be considered when providing medical advice.

Some of the important nutrients in this regard are protein and vitamins B6, B12 and D.


Girls need 0.9 g/kg/day of protein. For a person with a body weight of 60 kg, this corresponds to 54 g. The daily protein requirement of a person weighing 60 kg can be met by a vegan diet. According to Dörr, 54g of protein is contained in the following:

Vitamin B6

Vitamin B6 (pyridoxine) has, explains Dörr, multiple metabolic functions, especially in the metabolization of amino acids, and is important from a neurological point of view. For girls, the vitamin is important for hormonal metabolism. Data shows that about 14% of girls aged 14 to 18 ingest less than the recommended amount of vitamin B6. For vegans, the percentage of those with insufficient intake is even higher, because vitamin B6 has low bioavailability in foods of plant origin. For girls, there is also the added factor of oral contraceptives. There are indications that those using oral contraceptives containing estrogen have lower levels of pyridoxal-5′-phosphate (PLP), a marker of vitamin B6. Since PLP-dependent enzymes are also essential for the synthesis of hormones such as serotonin, symptoms such as depressed moods, increased irritability, nervousness and loss of libido may also indicate vitamin B6 deficiency. .

The daily B6 requirement for girls is 1.4 mg and can be met, for example, by consuming the following:

  • 200g hazelnuts

  • 200 g walnuts

  • 400g bananas (two to three bananas, depending on weight)

  • 700g cooked green beans

  • 1 kg cooked potatoes

  • 1.4 kg of oats.

Vitamin B12

Since vitamin B12 is not present in plant foods, following a vegan diet over the long term can lead to a deficiency unless you take dietary supplements. When researching the choices of various dietary supplements, it should be taken into account that the use of vitamin B12 from plant sources such as algae, algae and mushrooms is not necessarily a given. Careful selection and regular monitoring of B12 status are recommended.

Vitamin D

According to Dörr, evidence has grown in recent years that vitamin D is crucial not only for bones but also for many metabolic processes. The fact is that foods are barely able to meet vitamin D needs in the amounts one would expect to consume. Vegan foods cannot contribute to vitamin D intake, as considerable amounts are only present in foods of animal origin. The decision to take supplements and in what amounts should be made based on his condition.


Calcium, iodine, iron, seleniumand zinc are not readily available in sufficient quantities from a purely plant-based diet. Plant-based foods generally contain lower amounts of these minerals than animal-based foods, and plant-based minerals have lower bioavailability. According to Dörr, current evidence suggests that a vegan diet may have negative effects on bone health. In an ongoing cross-sectional study, ultrasound measurements of the heel bone are performed and biomarkers in blood and urine are measured. On average, people who follow a vegan diet have lower ultrasound readings than omnivores.

Britain’s European Prospective Investigation into Cancer and Nutrition (EPIC) study, which involved almost 55,000 people, found that vegans had a 43% higher risk of fracture than meat eaters.

An important nutrient, especially for cell development, is choline, which Dörr explains can be taken in primarily through the consumption of eggs, fish, meat and dairy products. There is growing evidence that a vegan diet is unable to provide sufficient amounts of choline, particularly if needs increase, such as during pregnancy and breastfeeding. It is increasingly clear that women who wish to conceive not only benefit from an adequate intake of folate intake for the prevention of neural tube defects and for favorable fetal development but also from sufficient quantities of choline (the recommended daily dose for pregnant women is 480 mg).

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