A vitamin B12 deficiency can lead to nerve and brain damage and anemia. Early symptoms include weakness, constipation, and depression. It can result from dietary factors, medication use, and some underlying conditions.
Without treatment, vitamin B12 deficiency can lead to anemia. It
This article looks at how to recognize B12 deficiency, who is at risk, and how to treat or prevent it.
Vitamin B12 is vital for creating and maintaining nerve and red blood cells, it supports the nervous system, and it helps create DNA, the basis of all cells.
The amount of vitamin B12 an individual needs per day will depend on their age. People also need more B12 during pregnancy and while breastfeeding.
The
| Age | B12 amount (mcg) |
|---|---|
| Birth to 6 months | 0.4 |
| 7 to 12 months | 0.5 |
| 1 to 3 years | 0.9 |
| 4 to 8 years | 1.2 |
| 9 to 13 yeras | 1.8 |
| 14 and over | 2.4 |
People’s vitamin B12 requirements are also higher during and after pregnancy. A pregnant person requires 2.6 mcg daily, while a lactating person requires 2.8 mcg.
A B12 deficiency can occur if a person does not consume enough of the vitamin in their diet or if their body cannot absorb it effectively during digestion.
Here are some possible
Pernicious anemia
Pernicious anemia is an autoimmune disease that affects the gut’s ability to digest vitamin B12.
When a person has pernicious anemia, their immune system creates antibodies that attack the stomach’s lining. There, they damage cells that produce intrinsic factor. If the stomach cannot produce intrinsic factor, the intestines will be unable to absorb vitamin B12.
2Bowel problems
Some people may have problems absorbing vitamin B12 into their bloodstream because of a condition that affects their stomach or small intestine. Possible causes include:
- Crohn’s disease
- celiac disease
- surgery that reduces the size of the stomach or the length of the intestine
These people can experience malnutrition because they cannot absorb enough vitamins, water, and other nutrients.
Diet
People who follow a vegan or vegetarian diet may have a higher risk of B12 deficiency. During pregnancy, this may increase the risk of neurological damage in a fetus.
Medications
Some medications can affect the body’s ability to digest vitamin B12, leading to a deficiency. Examples include proton pump inhibitors (PPIs) and Histamine H2 receptor agonists (H2 blockers), which doctors prescribe to treat indigestion, heartburn, and gastroesophageal reflux disease (GERD).
PPIs prevent the stomach from producing acid, but the body needs acid to absorb vitamin B12.
Metformin, a commonly prescribed medication for diabetes, is also associated with vitamin B12 deficiency
Functional vitamin B12 deficiency
Some people appear to have enough vitamin B12 in their blood, but they do not have the proteins they need to transport it between cells. This means the body cannot use it effectively.
They can develop neurological symptoms related to B12 deficiency.
A person with vitamin B12 deficiency may develop anemia and other symptoms.
Low levels of B12
- fatigue and weakness
- constipation
- loss of appetite and weight loss
- problems with balance
- depression
- problems with thinking
- a sore mouth or tongue
In infants, signs of a deficiency include:
- not growing or developing at the expected rate
- problems with movement
- megaloblastic anemia
Anemia and neurological problems can lead to further symptoms and complications.
Long-term B12 deficiency may increase the risk of various health problems. One reason for this may be that the body needs vitamin B12 to process homocysteine.
Experts have found
Dementia and thinking
Low levels of vitamin B12 may affect brain health in the long term and increase the risk of cognitive decline. Depending on the person’s age, it may
- reduced school performance in children
- irritability
- memory loss
- depression
- dementia
Neurological damage
Studies have shown that
- nerve damage
- damage to the spinal cord
- neurological problems that affect mental health
Cardiovascular disease
Experts have also found high levels of homocysteine in people with coronary heart disease and stroke.
However, there is not enough evidence to recommend B12 supplementation to prevent heart disease.
Energy levels
Some people use B12 supplements to boost energy levels and athletic performance. However, supplements only
To assess for a vitamin B12 deficiency, a doctor will likely:
- ask about symptoms
- carry out a physical examination
- do a blood test to measure B12 levels and check for anemia
- do other tests to rule out other conditions and check for pernicious anemia, if necessary
Some people will have a B12 deficiency but no symptoms. A doctor may recommend regular testing for people with long-term gastrointestinal problems to ensure a deficiency does not develop.
Getting an early diagnosis can help prevent long-term complications.
Treatment will depend largely on the cause of a deficiency. Options include increasing vitamin B12 intake through:
- intramuscular injections
- oral medicine
- adding foods that are rich in B12 to the diet
Some people may need regular injections for the rest of their life.
Good sources of vitamin B12 include the following:
- clams
- beef liver
- fish, such as trout, salmon, and tuna
- nutritional yeast
- dairy products
- eggs
- fortified yeasts and other foods
Most people can prevent B12 deficiency through dietary choices, but this is not always true. Certain groups may require additional considerations to prevent a B12 deficiency.
Medical conditions
Anyone with anemia, a chronic gastrointestinal condition, or other condition affecting B12 absorption should defer to a medical professional for treatment advice. Doctors may recommend supplementation, medications, and other changes.
People following a plant-based diet
People whose diet is largely or wholly plant-based may require additional considerations to ensure their B12 intake is adequate. Dietary options include:
- fortified breakfast cereals
- fortified nutritional yeast
- fortified soy milk
Older adults
As people age, their ability to absorb vitamin B12 can decrease. In these instances, prioritizing a diet rich in B12, or taking supplements can help people reach the necessary intake.
Vitamin B12 is essential for preventing anemia and maintaining neurological health. It may help prevent dementia and heart disease.
A balanced diet can often help prevent a deficiency. People who eat only plant-based foods may consider including fortified foods or asking a doctor about supplements.
A doctor may also recommend supplements if a person has pernicious anemia, Crohn’s disease, or another condition that affects their ability to absorb vitamin B12.