Vitamin B12 deficiency is common, especially among vegetarians and older adults.
Also known as cobalamin,vitamin B12is a water-soluble vitamin found in meat, fish, and dairy.
Vitamin B12 is essential for brain and nerve function.
Verywell / Luyi Wang
A vitamin B12 deficiency can cause headaches,fatigue, muscle weakness, and depression.
Diagnosing vitamin B12 deficiency can be tricky because the symptoms are similar to other health conditions.
This article looks at the symptoms, causes, and diagnosis of vitamin B12 deficiency.
It also discusses treatment for vitamin B12 deficiency.
Vitamin B12 Deficiency Symptoms
Vitamin B12 plays a complex role in your body.
This is why B12 deficiency has so many potential symptoms.
There are four main categories of vitamin B12 complications.
A complication is a problem because of a medical condition or treatment.
These categories can cause a range of symptoms.
Many of these symptoms are also found in other conditions.
This is why it can be difficult to diagnose vitamin B12 deficiency.
Anemia
Vitamin B12 plays a role in the production of red blood cells (RBCs).
These cells carry oxygen through the body.
Oxygen helps your body produce energy.
Vitamin B12 deficiency leads to defective RBCs.
This causesanemia.Anemia can make you feel weak and fatigued.
Neuropathy
Vitamin B12 is also a vital part of a healthy nervous system.
This is calledneuropathy, an impairment in nerve function.
These symptoms can be worse if you also have anemia.
Myelopathy
Myelopathyis an impairment of thespinal cord.
This results in muscle weakness.
It can also cause difficulties in sensing light touch and vibration.
People with myelopathy may also have problems withproprioception.
People with this condition may also have neuropathy-like symptoms.
Dementia
Vitamin B12 deficiency may causedementia.
They do not usually improve without treatment.
What Causes Vitamin B12 Deficiency?
Vitamin B12 deficiency has two primary causes.
Some people do not get enough B12 in their diet.
Others have problems absorbing B12 in the intestines.
Inadequate Intake
Vitamin B12 is found in manyfood sources.
These include:
Many sources of vitamin B12 come from animal proteins.
The risk is also higher in the elderly and people who abuse alcohol.
Impaired Absorption
Vitamin B12 is absorbed in the gut with the help of a protein calledintrinsic factor.
When the process of absorption doesn’t work right, you may develop B12 deficiency.
This is because many of the common symptoms overlap with those of other health conditions.
Your medical team may consider a number of diagnoses besides B12 deficiency.
History and Physical Examination
Your medical history can help your doctor understand your symptoms.
A physical exam may also help identify the signs of B12 deficiency.
For example, a weak, rapid pulse or pale fingers may be a sign of anemia.
Signs of neuropathy can include low sensation in your feet and poor reflexes.
Confusion or trouble communicating are common signs of dementia.
Laboratory Tests
Laboratory tests can confirm your diagnosis.
These tests include acomplete blood count (CBC)and a vitamin B12 level.
B12 deficiency is associated with a particular jot down of anemia.
Imaging and Specialized Tests
Other tests can be used to help confirm a diagnosis.
These includenerve conduction studies, which measure the speed of the electrical signals in your nerves.
These tests can’t confirm B12 deficiency on their own, though.
This is why they are usually used alongside other diagnostic tools.
How Vitamin B12 Deficiency Is Treated
Vitamin B12 deficiency can be managed withsupplemental B12.
The injection will help the vitamin absorb directly into your body.
Some patients need lifelong B12 supplementation.
This usually depends on the cause of the deficiency.
You may need to continue taking B12 supplements even after your symptoms improve.
How Long Does It Take to Recover From Vitamin B12 Deficiency?
Recovery from vitamin B12 deficiency takes time.
You may not have any improvement during the first few months of treatment.
Improvement may be gradual and may continue for up to six to 12 months.
Rehabilitation
You may have long-lasting symptoms even after treatment.
Numbness, tingling, and weakness can impair your balance.
Aphysical or occupational therapistcan help you develop strategies to cope with these long-term problems.
Memory problems can improve as your vitamin B12 levels are corrected.
Still, you may have some deficits in your thinking skills for a long time.
Cognitive rehabilitation and therapy can help you improve your thinking and problem-solving skills.
Many of these symptoms can be confused with other conditions, making vitamin B12 deficiency hard to diagnose.
The two primary causes of B12 deficiency are low B12 levels in the diet and problems absorbing the vitamin.
Vitamin B12 deficiency is diagnosed with a medical history, exam, laboratory tests, and other tests.
It is usually treated with supplemental B12.
You may need long-term rehabilitation after treatment in order for your symptoms to improve.
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