10 Neurological symptoms of vitamin B12 deficiency

June 3, 2022

10 Neurological symptoms of vitamin B12 deficiency
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For functions like DNA synthesis, energy production, and central nervous system health, your body needs vitamin B12.

Despite the fact that B12 is present in many meals, deficiencies and insufficiencies are very prevalent. This is frequently brought on by inadequate food intake, malabsorption, specific illnesses, or B12-depleting drugs.

For reference, B12 levels above 300 pg/mL are regarded, as usual, concentrations between 200 and 300 pg/mL are regarded as borderline, and those below 200 pg/mL are considered inadequate.

This article discusses nine of the most typical B12 deficient symptoms and how this deficiency is diagnosed and treated.

1. Fatigue

You might experience fatigue if your B12 levels are low or inadequate.

B12 is required for healthy cell function in your body. As a result, low B12 levels can reduce the creation of healthy red blood cells, reducing oxygen supply.

Particularly, megaloblastic anemia can be brought on by a B12 or folate deficit. Large, abnormal, immature red blood cells are produced due to this disease, which also affects DNA synthesis.

You’ll probably feel weak and exhausted if your body doesn’t have healthy red blood cells to transport oxygen to tissues.

It’s crucial to understand that even when your B12 levels are regarded as normal or borderline low, you might still experience fatigue and other symptoms linked to a B12 shortage.

2. Pale or Yellowish skin

Another sign that may indicate a B-12 deficiency is pale or yellow skin. Like the condition called iron-deficiency anemia, anaemia related to B12 deficiency can turn your skin pale due to a lack of fully-matured, healthy red blood cells in the body.

B12 deficiency can also cause jaundice, which causes your skin and the whites of your eyes to turn yellowish. High bilirubin levels cause the color, a waste product produced when your body breaks down red blood cells.

3. Headache

B12 insufficiency and deficiency can lead to neurological side effects, including headaches. Headaches are one of the most commonly reported symptoms of B12 deficiency in adults and kids. In addition, some studies suggest that people who regularly experience inevitable headaches are more likely to have low vitamin B12 levels. For example, a 2019 study of 140 people, half of whom had migraines, found that migraine sufferers had significantly lower levels of B12 in their blood compared to participants with no history of migraines. The study also found that those with the highest levels of B12 were 80% less likely to have migraines than participants with the lowest levels of B12.

4. Depressive symptoms

A B12 insufficiency can have an adverse effect on your mental health because B12 is necessary for the healthy operation of your central nervous system.

A lack of B12 is particularly linked to a higher risk of developing depression.

Homocysteine, a sulfur-containing amino acid, can be raised when B12 levels are low. As a result, the body may experience more oxidative stress, DNA damage, and cell death, which could eventually lead to the onset of depression.

Low B12 levels can cause mood problems and psychosis, in addition to depression symptoms in the brain.

5. Gastrointestinal Issues

A deficiency may cause diarrhoea, nausea, constipation, bloating, gas, and other gastrointestinal symptoms. Many of these symptoms could be caused by food intolerances, medications, and infections.

6. Having trouble focusing and having a mental impairment

People with low B12 levels may experience mental fogginess, difficulty concentrating, and difficulty accomplishing tasks because a B12 deficiency negatively affects the central nervous system.

Because the risk of B12 insufficiency rises with age, older persons are particularly vulnerable to these negative effects.

Numerous studies have linked worsening mental health in elderly persons and low B12 levels.

Furthermore, research has found that B12 supplementation helps relieve mental impairment caused by low B12 levels.

For instance, in a 2020 research, B12 replacement therapy was administered for three months to 202 individuals with minor mental impairment, low or low-normal B12 levels, and increased homocysteine levels.

Eighty-four per cent of the patients said their symptoms, such as trouble concentrating and memory loss, had significantly improved after the therapy.

Also Read: Carotid Endarterectomy (CEA)

Other problems

B12 insufficiency may cause the following in addition to the symptoms mentioned above:

7. Weakness and cramping in the muscles:

Muscle cramps and weakness may result from impaired motor and sensory nerve function caused by a B12 deficiency.

8. Lack of cooperation:

A neurological sign of a B12 deficiency is ataxia, or poor balance and coordination. A B12 shortage can make it difficult to walk and balance.

9. Erectile Dysfunction:

Increased homocysteine levels in the body might cause erectile dysfunction in men with a B12 deficiency.

10. Disruptions to vision:

Vision problems could result from B12 deficiency because it damages the optic nerve.

How is it diagnosed and treated?

The symptoms of vitamin B12 insufficiency aren’t unique to the disorder; thus, it could go unnoticed or get misdiagnosed.

It is crucial to address your symptoms with a healthcare provider if you suffer any of the signs mentioned above and symptoms.

This is particularly important if you:

  • Are over 60 and maintain a stringent diet, such as a vegan diet
  • Are breastfeeding or pregnant
  • A medical condition that could cause B12 levels to drop
  • Use medicine that depletes B12, such as metformin or proton pump inhibitors

Also Read: Importance Of A Balanced Diet

A healthcare provider can exclude a B12 deficiency after hearing about your symptoms, performing a physical examination, and obtaining a blood test. These tests may consist of

  • B12 levels
  • Folate levels
  • A peripheral smear with a complete blood count (CBC)
  • Amounts of methylmalonic acid (MMA)

Your doctor will advise the best course of action if it is determined that your B12 levels are too low. B12 injections, oral B12 supplements, or treating an underlying medical issue that might be the source of the deficit are a few options. People who can’t adequately absorb B12 through food or supplements, such as those who’ve had gastric bypass surgery or those with certain autoimmune illnesses, are typically advised to have B12 injections.

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People also ask

1. What happens when your B12 is deficient?

Diarrhea, appetite loss, constipation, or gas. Muscle weakness, issues with walking, and nerve issues, including numbness or tingling. Loss of vision such as memory loss, depression, or behavioral abnormalities.

2. What are the classic neurologic features of vitamin B12 deficiency?

Sensory or motor deficits, subacute combined spinal cord degeneration, or seizures are examples of neurological symptoms. In addition, cognitive deficits, regression, irritability, involuntary movements, and hypotonia indicate deficiencies in children.

3. Can low B12 affect your nerves?

A lack of vitamin B12 can cause neurological problems, such as blurred vision, affecting your nervous system. Memory loss. pins and needles (paresthesia)

4. Can B12 deficiency make you feel weird?

Dementia, depression, confusion, memory issues, and dementia may result from a B12 deficiency. Your balance may be affected as well.

Disclaimer: We recommend consulting a Doctor before taking any action based on the above shared information.



Department of Neurology

Department of Neurology

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