Vitamin B12 deficiency and its consequences
Vitamin B12 deficiency occurs when the body doesn't get or absorb enough of this essential vitamin. It can lead to fatigue, nerve damage, and concentration problems. Since B12 is mainly found in animal products, vegetarians, vegans, and older adults are especially at risk. Early detection and proper supplementation can prevent long-term health issues.
Vitamin B12, also known as cobalamin, is a water-soluble vitamin essential for many metabolic processes in the body. It supports:
According to the guidelines of the German Nutrition Society (DGE), healthy people aged 15 and over should consume around 4.0 micrograms (µg) of vitamin B12 daily. Pregnant and lactating women require higher amounts: 4.5 µg and 5.5 µg, respectively.
A deficiency occurs when:
Other causes include:
A vitamin B12 deficiency can have very different causes, including:
Because the body can't produce vitamin B12 itself, we have to take it in with food. B12 is mainly found in meat and fish, but also in eggs and dairy products, but in much smaller quantities. Especially vegetarians and vegans don't get enough of the classic B12 sources.
If you are pregnant or breastfeeding or under persistently high stress, you need significantly more vitamin B12. You should adjust your diet accordingly or use appropriate preparations.
Because vitamin B12 enters the body through the gastrointestinal tract, chronic and acute diseases of the gastrointestinal tract restrict B12 supply. Your body can't absorb enough vitamin B12, for example in diseases such as ulcerative colitis or Crohn's disease, gastritis, celiac disease or pernicious anemia, which destroys the stomach lining
In old age, several factors can promote a B12 deficiency.
Certain groups of people are particularly vulnerable to a lack of B12. These are:
The symptoms of a vitamin B12 deficiency often only appear after a few years, because a healthy person can store cobalamin in the liver for up to three years. The shortage only becomes noticeable when the reserves are used up. At first, the symptoms are rather inconspicuous and very diverse. They do not always lead to the correct conclusion straight away.
These signs can indicate a vitamin B12 deficiency:
The following symptoms also often occur:
A temporary vitamin B12 deficiency is not life-threatening if it is diagnosed early. The doctor can determine the deficiency in different tests, including:
If you suspect a vitamin B12 deficiency, a blood test is recommended first. The value of the cobalamin in the blood is determined. Even if this value is still just within the normal range, you can't rule out a B12 deficiency, especially if you are a senior citizen.
Then the Holo-TC (Holo-Transcobalamin) test is recommended. It is a version of the B12 that transports the nutrient from your blood into the cells. A blood test has shown sufficient cobalamin, but that alone is not yet meaningful enough.
A good option is also a urine test. Your morning urine will be examined for methylmalonic acid. If this value is too high, this indicates a vitamin B12 deficiency.
Vitamin B12 is mainly found in animal-based foods. Here's a breakdown of rich sources:
Animal-Based Sources (Best Natural Sources)
Vegetarian Sources (Moderate B12 content)
Vegan Diets
Vitamin B12 is rarely found in plant-based foods, but some trace sources include:
Note: These vegan sources are not reliable to meet daily needs. Supplementation is usually necessary for vegans.
Vitamin B12 deficiency can be effectively treated using various Vitamin B12 supplementation methods, tailored to the severity of the deficiency and individual absorption needs.
1. Reason for Supplementation
2. Absorption Ability
3. Form of Vitamin B12
4. Duration of Treatment
5. Safety and Side Effects
6. Special Populations
For more details, check out our comprehensive blog on Vitamin B12, covering its effects, side effects, food sources, dosage recommendations, and risks of overdose.
Recommended products
Related blogs
Vitamin B12 - What you should know!
Vitamin B12 is an essential and water-soluble vitamin that fulfils many important functions in the body. This includes the support in the production of red blood cells, as well as in the development and function of the nervous system. Vitamin B12 is ingested through food; vitamin B12 is only present in food of animal origin. Vegans and vegetarians are therefore particularly at risk of suffering from a vitamin B12 deficiency. This also applies to older people, as the ability to absorb and utilise vitamin B12 from food decreases with age.