Vitamin B12 is involved in many important processes in the body and a vitamin B12 deficiency can have far-reaching consequences. Vegetarian and vegan people are particularly at risk here, warns the Federal Institute for Risk Assessment (BfR).
Since relevant amounts of vitamin B12 are only contained in foods of animal origin, people with a vegetarian or vegan diet must pay particular attention to their vitamin B12 supply and, if necessary, take appropriate dietary supplements, according to the BfR.
Intake through diet
As the experts explain, vitamin B12 is involved in various metabolic processes, supports the formation of red blood cells, cell division and the regeneration of nerve cells. However, for an adequate supply, the vitamin must be supplied through the diet.
However, significant amounts of the vitamin are naturally only contained in foods of animal origin, because vitamin B12 is synthesized by bacteria in the animals’ digestive tract. According to the BfR, it contains a particularly high amount of vitamin B12
- red muscle meat,
- and dairy products.
Likewise, some bacterially fermented plant foods such as sauerkraut or certain sea algae and shiitake mushrooms contain traces of vitamin B12. But all other conventional plant-based foods do not contain vitamin B12.
Who should supplement vitamin B12?
Therefore, it is not possible for humans to meet their needs with plant-based foods alone, which is why vegans in particular, but also vegetarians, should supplement vitamin B12 after consulting a doctor, explains the BfR.
The daily requirement for vitamin B12 is four micrograms (μg) for children aged 13 and over, adolescents and adults, although women who are pregnant and breastfeeding have a slightly higher requirement (4.5 and 5.5 μg/day), according to reports the BfR citing the recommendations of the German Nutrition Society (DGE).
If too little vitamin B12 is absorbed or the absorption in the body is impaired, there is a risk of a vitamin B12 deficiency, which initially affects the metabolic processes supported by the vitamin, the BfR continues.
Signs of vitamin B12 deficiency
Accordingly, the deficiency impairs blood formation and this can lead to anemia, which is accompanied by symptoms such as paleness, tiredness, tingling or numbness in the limbs.
Neurological and psychological disorders (weak memory or depressive moods) and gastrointestinal disorders (e.g. burning tongue, loss of appetite, constipation) are also possible consequences.
Overall, it’s important to recognize the signs of vitamin 12 deficiency to prevent irreversible damage. It should also be borne in mind that the deficiency often only occurs after years of deficient intake because the body can draw on its reserves over a longer period of time.
“After about one to four years of a vitamin B12-free diet, the vitamin B12 stores in the liver are depleted by half; Only when the storage level has fallen to a level of 5 to 10 percent do the first clinical symptoms appear,” reports the BfR.
Maximum limit dietary supplement recommended
In order to prevent a deficiency, vegetarians and vegans are recommended to have their vitamin B12 status regularly checked by a doctor and to take dietary supplements containing vitamin B12.
According to the BfR, however, dietary supplements should contain a maximum of 25 micrograms of vitamin B12 per daily dose. Epidemiological studies have suggested that long-term intake of high amounts of vitamin B12 could have undesirable health effects. (fp)