4 min

The 6 signs of a Vitamin B12 deficiency

The article in a few key points

Vitamin B12 is a nutrient that is not produced by the body. It is obtained from our diet (mainly in products of animal origin) or by taking supplements.

A vitamin B12 deficiency can manifest itself through various symptoms: fatigue, shortness of breath, feeling of weakness, muscle cramps, etc.

In order not to be deficient, it is important to maintain good vitamin B12 intake, particularly among vegetarians and vegans.

Vitamin B12 is one of the essential vitamins and minerals, which are not synthesized by the body, and must therefore be supplied entirely through food.
It plays several roles: it contributes in particular to maintaining a satisfactory energy level in the body, to regulating the formation of red blood cells in the blood and to promoting effective immune defenses.

Vitamin B12 is mainly found in meats and offal, certain types of shellfish and fish, and certain cheeses. Therefore, vitamin B12 food supplements are particularly recommended for vegans, because the majority of natural sources of B12 are of animal origin.

Vegan or not, how do you know if you have a vitamin B12 deficiency? Here are 6 symptoms of a potential B12 deficiency.

1) Fatigue, shortness of breath: anemia due to lack of vitamin B12

This is the most well-known and likely symptom of vitamin B12 deficiency. This helps ensure a normal level of red blood cells in the blood. If there is a lack of B12, there may be an insufficient number of red blood cells, which is called anemia. It leads to a loss of energy, chronic fatigue, and an overall feeling of weakness. Anemia can even lead to dizziness, and requires supplementation (with vitamin B12 and/or iron, in particular) to resolve quickly.

2) Muscle cramps

Among its many actions, vitamin B12 also intervenes in the functioning of the nervous system. If you are often subject to cramps, especially during your sleep, it is because you may be deficient in B12.

A cramp is a sudden and involuntary contraction of a muscle, which occurs due to excessive excitability of the muscle or nerves. If nerves are the cause, it is potentially because your nervous system is not functioning completely normally: supplementing with vitamin B12 can then help you remedy the situation.

3) Loss of appetite and mouth ulcers

Lack of vitamin B12 can lead to loss of appetite, as well as mouth ulcers and other symptoms visible in your mouth. A swollen, red and/or painful tongue, or even atrophied taste buds can alert you to a B12 deficiency.

vitamin B12 deficiency

4) Brain problems and memory problems

Vitamin B12 has direct influences on psychology and cognitive abilities. Too little B12 can therefore lead to memory loss or, in the most serious cases, symptoms similar to Alzheimer's or dementia, such as hallucinations. It is also to partly compensate for this that vitamin B12 supplementation is also indicated for the elderly.

5) Irritability due to vitamin B12 deficiency

Another possible mental consequence of a lack of B12: irritability and bad mood. Some affected people lose their temper a little too easily, becoming abnormally irascible, even confused or depressed.

6) Constipation and stomach problems

Vitamin B12 deficiencies can finally result in various digestive symptoms and disorders: vomiting, nausea, constipation, flatulence, and even abdominal pain.

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