Vitamin B12 is vital for humans: It plays an important role in various metabolic processes, is involved in the breakdown of certain fatty acids, supports blood formation and is important for normal nerve function. And it is also needed in the genome for the production of DNA. There is not “the one” vitamin B12; the name is a collective term for various compounds with the same chemical building blocks, the so-called cobalamins. That is why medicine also speaks of cobalamin when it comes to vitamin B12.
We humans mostly get vitamin B12 in our food. It is bound to animal proteins. Therefore, under certain circumstances, a vegetarian or vegan lifestyle can lead to vitamin B12 deficiency. A lack of cobalamin can be dangerous – but you can counteract the deficiency with the right diet or an additional intake of vitamin B12.
How much vitamin B12 is needed?
How much vitamin B12 the body needs depends on age. According to the German Society for Nutrition (DGE), the estimated values for an adequate vitamin B12 intake during childhood increase from 0.5 micrograms per day for infants to 4.0 micrograms per day for adolescents aged 13 and over. The same value applies to adults. Pregnant and breastfeeding women have an increased need. A reasonable daily dose is 4.5 micrograms for pregnant women and 5.5 micrograms for breastfeeding women.
Vitamin B12 deficiency: typical symptoms
If these values are not reached, depending on the severity of the vitamin deficiency show different symptoms:
- fatigue and weakness
- pale skin tone
- lower efficiency
- depressed moods
- forgetfulness
- headache
- dizziness
- yellowish skin
- chest pain, difficulty breathing
- mouth ulcers
- shortness of breath
- burning tongue
- Tingling or numbness, especially in the legs
- problems walking
- impotence
- in the unborn: malformations
- in infants: developmental delay, low blood pressure, tremors or convulsions
- in the elderly: nerve damage and dementia
Since vitamin B12 is also necessary for the formation of red blood cells, a vitamin B12 deficiency can lead to anemia. Anemia is also called anaemia. The medical encyclopedia “MSD Manual” writes: “It may not develop until three to five years after the onset of the deficiency, since a large amount of vitamin B12 is stored in the liver.” The vitamin is mostly stored in the liver, to a lesser extent in the kidneys, muscles, brain and spleen.
However, the DGE warns that people without a previously adequate vitamin B12 supply can feel deficiency symptoms much earlier. This happens, for example, with breastfed infants whose mothers eat a vegan diet during pregnancy and breastfeeding and whose vitamin B12 supply is not sufficiently guaranteed.
Causes of vitamin B12 deficiency
For the deficiencies the “MSD Manual” sees two main causes: Either the body does not get enough vitamin B12 or it does not absorb the vitamin or does not store sufficient amounts of it.
Vitamin B12 can only be produced by microorganisms. Via the food chain, it reaches the animal and then the human organism. People who do not eat any products of animal origin – i.e. eat vegan food – therefore have a hard time getting this vital substance.You should take extra care to get enough B12. Chronic alcohol consumption can also lead to vitamin B12 deficiency.
However, some people have problems absorbing or storing cobalamins despite animal nutrition. That medical information portal “Neurologienetz” gives various reasons for this, including chronic gastritis (especially in old age), diseases of the small intestine, problems with the pancreas, or the consequences of surgical interventions in the gastrointestinal tract.
According to “neurology network” lead to B12 deficiency.
Elderly people may also not be able to absorb enough vitamins because they produce stomach acid. “Decreased stomach acid reduces the body’s ability to remove vitamin B12 from meat protein,” explains the MSD Manual.
Diagnosis: How is a vitamin B12 deficiency detected?
Anyone who eats only plant-based foods should have their vitamin B12 supply checked regularly by a doctor. In order to determine a vitamin B12 deficiency, a doctor usually does a blood test. If a routine blood test shows enlarged red blood cells beforehand, this is a sign of the deficiency. If typical symptoms (as described above) are already evident, it is also advisable to measure the vitamin B12 level in the blood.
Especially in younger people, a confirmed B12 deficiency is followed by further tests and investigations to find the cause of the low level.
Prevention and treatment of vitamin B12 deficiency
People who neither suffer from absorption disorders nor follow a vegan diet, a balanced diet is sufficientto get enough B12. Good vitamin B12 suppliers are meat, fish and seafood as well as eggs and dairy products such as yoghurt. Vegetarians can get the vitamin in the form of seaweed, certain types of mushrooms, and products containing cyanobacteria. According to the DGE, however, the amounts of vitamin B12 contained can vary enormously.
Otherwise, the following applies: Both the prevention and the treatment of a vitamin B12 deficiency works via the Taking B12 supplements. Older people who produce too little stomach acid to absorb vitamin B12 can easily absorb the vitamin from the supplements. Dietary supplements are usually swallowed as tablets or capsules. Since their vitamin B12 content can also be produced from algae, there are purely plant-based alternatives for vegans and vegetarians.
If severe symptoms such as nerve damage or anemia occur, the high-dose B12 can also be injected directly into a muscle. These injections, which patients can also self-administer, are injected daily or weekly for several weeks. At some point, the vitamin B12 level normalizes.
Vitamin B12: Is an overdose possible?
What Happens When You Take Too Much Vitamin B12? The DGE writes: “According to current knowledge, a high intake of vitamin B12, which occurs naturally in food, is not harmful.” And according to the “MSD Manual”, excessive intake of B12 supplements does not cause any damage either. If there is too much vitamin B12 in the food, the body will not automatically absorb more of it. He excretes the vitamin – as well as in the case of a Vitamin C overdose or an overdose of vitamin D – just off. But that also means: High-dose dietary supplements therefore bring no additional health benefit.