Lack of vitamin B12 causes physical and psychological symptoms

It is estimated that about 40% of the world population has low amounts of B12. However, this deficiency does not always present symptoms and is often never diagnosed.

As with other nutritional deficiencies, the lack of vitamin B12 can cause damage to the body, hinder the proper functioning and bring complications to health.

It is worth mentioning that the nutrient stocks are, in general, durable, so even if there is no daily consumption of the vitamin, the organism’s rates can remain stable.


What are the normal levels of vitamin B12?

The reference value of B12 is between 200pg / mL and 900pg / mL. However, the classifications of vitamin insufficiency vary widely according to each researcher or laboratory.

While there are studies that suggest a deficiency below 200pg / mL, others indicate that up to 500pg / mL can already be considered a low value.

When performing blood tests, the reference values ​​generally used by laboratories are:

  • Severe deficiency : below 150 pg / mL;
  • Deficiency : between 150pg / mL and 200pg / mL;
  • Possibility of deficiency : 200pg / mL and 300 pg / mL;
  • Normal levels : between 300pg / mL and 900 pg / mL;
  • Hypervitaminosis : above 1000pg / mL.

The values ​​should then be evaluated with your doctor who will also consider the presence of symptoms and other nutritional deficiencies, checking the need to readjust the diet or start supplementation with B12.

What are the symptoms of lack of vitamin B12?

The symptoms of low levels of B12 are widespread and do not always allow them to be associated with hypovitaminosis. But there are usually changes in mood ( tiredness and weakness), neurological signs (numbness and tingling in the hands and legs), as well as anemia .

In general, the first signs can involve constant tiredness, mood swings, reduced immunity and inflammation of the mouth. If levels continue to drop, reaching severely low values, the body’s functions are affected, with a reduction in DNA synthesis and an increase in homocysteine ​​(amino acid) in the blood.

Other symptoms can occur, such as:

Psychological symptoms

Low B12 rates can impact emotional and nervous well-being, with:

  • Irritability;
  • Difficulty concentrating;
  • Memory changes;
  • Sudden changes in mood;
  • Depression and severe anxiety;
  • Lethargy;
  • Mental confusion;
  • Hallucinations.

Physical symptoms

The physical signs that the patient may present involve:

  • Drop in immunity (leaving the patient more prone to flu and infections);
  • Frequent tiredness, even without great efforts;
  • Weakening of nails and brittle hair;
  • Pallor;
  • Ulcerations in the mouth (small whitish wounds);
  • Inflammation in the mouth and stomach pain (due to gastrointestinal ulcers);
  • Megaloblastic anemia (increase in the volume of red blood cells);
  • Pains and tingles in the arms and legs;
  • Difficulty moving;
  • Dizziness and dizziness;
  • Heart attack;
  • Stroke;
  • Difficulty and reduced vision;
  • Urinary and fecal incontinence;
  • Fertility problems.