Vitamin B12 Deficiency: How Long Until You Recover?

Jul 01, 2024 | 7 min read

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Understanding how long to recover from vitamin B12 deficiency is crucial, as causes like poor diet, certain medical conditions, and aging can lead to severe health issues. Recovery typically takes from a few months to a year. Managing this condition with proper diagnosis and treatment is essential for a swift recovery and long-term health.

how long to recover from vitamin b12 deficiency

What is Vitamin B12?

Vitamin B12, or cobalamin, is essential for healthy nerve tissue, red blood cell production, and brain function. Without enough vitamin B12, various health issues can arise, including anemia, nerve damage, and cognitive problems.

Vitamin B12 also maintains the myelin sheath, the protective covering around nerves, ensuring efficient nerve signal transmission. A deficiency can cause numbness, tingling, and balance problems.

Additionally, vitamin B12 is crucial for brain function, helping produce neurotransmitters. Adequate levels support memory and thinking, while a deficiency can lead to memory problems and depression.

Causes of Vitamin B12 Deficiency


Dietary choices significantly impact vitamin B12 levels. Since vitamin B12 is primarily found in animal products, individuals who follow vegetarian or vegan diets are at a higher risk of deficiency. Plant-based foods typically do not contain sufficient amounts of vitamin B12 unless they are fortified. Therefore, people on such diets need to find alternative sources of B12, such as supplements or fortified foods, to meet their nutritional needs.

Medical Conditions

Several medical conditions can interfere with the body's ability to absorb vitamin B12, leading to deficiency.

  • Pernicious Anemia: This is an autoimmune disorder that affects the stomach lining, reducing the production of intrinsic factor, a protein necessary for vitamin B12 absorption. Without enough intrinsic factor, the body cannot effectively absorb vitamin B12 from food.
  • Digestive Disorders: Conditions such as Crohn's disease, celiac disease, and other inflammatory bowel diseases can damage the part of the intestine that absorbs vitamin B12. This damage hinders the absorption process, leading to deficiency.
  • Liver Problems: The liver stores a significant amount of vitamin B12. Liver diseases can disrupt the storage and metabolism of this vitamin, leading to deficiency.

Age and Lifestyle Factors

Various age and lifestyle factors can also contribute to vitamin B12 deficiency. According to a study published in the NCBI, up to 15% of the general population has a vitamin B12 deficiency. This rate is higher in certain groups, such as vegetarians, vegans, and older adults. Other causes include: 

  • Aging: As people age, their bodies produce less stomach acid, which is necessary for vitamin B12 absorption. This reduction increases the risk of deficiency in older adults.
  • Alcohol Misuse: Excessive alcohol consumption can interfere with the absorption of vitamin B12 and reduce the amount of the nutrient in the diet, leading to deficiency.
  • Certain Medications: Some medications, such as those used to treat diabetes and acid reflux, can affect the absorption of vitamin B12.
  • Surgical Procedures: Surgeries involving the stomach, such as gastric bypass surgery, can reduce the number of cells that produce intrinsic factor, thus hindering B12 absorption.

Symptoms of Vitamin B12 Deficiency

General Symptoms

Vitamin B12 deficiency can present a range of symptoms that vary in severity. Early detection and treatment are essential to prevent long-term health issues. Here are some general symptoms to watch out for:

  • Fatigue: Feeling excessively tired and lacking energy is a common sign of vitamin B12 deficiency. This occurs because the body does not have enough red blood cells to carry adequate oxygen to tissues.
  • Difficulty Focusing: Cognitive functions like concentration and focus can be impaired. This might make daily tasks and work more challenging.
  • Memory Problems: Short-term memory issues and forgetfulness are often linked to low levels of vitamin B12.
  • Mood Swings: Changes in mood, including increased irritability and depression, can be symptoms of a deficiency.
  • Feeling Cold: Persistent feelings of coldness, especially in the hands and feet, can be a symptom due to reduced red blood cell production and anemia.
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Symptoms and Specific Conditions

Condition Symptoms
Anemia Fatigue, dizziness, paleness, rapid heart rate
Neuropathy Balance problems, weakness, numbness, tingling
Myelopathy Sensory problems, tingling, numbness
Dementia Behavioral changes, cognitive decline

Recognizing these symptoms early and seeking medical advice can help manage and treat vitamin B12 deficiency effectively.

Diagnosing Vitamin B12 Deficiency

Medical History and Physical Examination

Diagnosing vitamin B12 deficiency involves reviewing your medical history and a physical examination. Discuss your diet, medications, and health conditions with your doctor to identify potential causes of the deficiency. For example, vegetarian or vegan diets, gastric surgery, or conditions like Crohn's disease or celiac disease increase your risk.

During the physical exam, the doctor will check for signs like pale skin, a rapid pulse, and neurological symptoms such as numbness or tingling. These signs can indicate anemia or nerve damage, common in vitamin B12 deficiency.

Laboratory Tests

Laboratory tests are essential to confirm a vitamin B12 deficiency diagnosis. The most common tests include:

  • Blood Tests: These measure the levels of vitamin B12 in the blood. Normal values range from 160 to 950 picograms per milliliter (pg/mL) or 118 to 701 picomoles per liter (pmol/L), though these ranges may vary slightly among different laboratories, as per Mount Sinai. Blood tests can also measure levels of methylmalonic acid (MMA) and homocysteine, which are usually elevated in B12 deficiency.
  • Complete Blood Count (CBC): This test evaluates the overall health of your blood, including red and white blood cells and platelets. It can help detect macrocytic anemia, a condition where red blood cells are larger than normal, which is often associated with vitamin B12 deficiency.
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Specialized Tests

In some cases, additional tests may be necessary to confirm the diagnosis or assess the extent of the deficiency:

  • Nerve Conduction Studies: These tests measure the speed and strength of signals traveling through the nerves. They can help detect neuropathy caused by vitamin B12 deficiency.
  • Bone Marrow Biopsy: In rare cases, a biopsy may be performed to examine the bone marrow if the diagnosis remains uncertain after initial tests.

Early diagnosis and treatment are critical to prevent irreversible damage caused by prolonged vitamin B12 deficiency. Regular check-ups and communication with your healthcare provider can help maintain adequate vitamin B12 levels and overall health.

Recovery Time for Vitamin B12 Deficiency

Recovery from vitamin B12 deficiency typically takes a few months to a year, depending on the severity of the deficiency and the treatment method used. Here is a breakdown of the recovery timeline:

  • Mild Deficiency: If caught early, recovery can begin within a few weeks, with noticeable improvements in energy levels and cognitive function. Full recovery usually occurs within three to six months.
  • Moderate Deficiency: For those with more significant symptoms, such as anemia or mild nerve damage, recovery may take longer. Most individuals see substantial improvements within three to six months, but full recovery may take up to nine months.
  • Severe Deficiency: In cases of severe deficiency with significant nerve damage or long-term anemia, recovery can be more gradual. Patients might start to feel better within a few months, but complete recovery can take up to a year or more, especially if nerve damage is extensive.

Factors Affecting Recovery

  • Severity of Deficiency: Those with a more severe deficiency may require longer treatment periods before seeing significant improvements. Severe cases often involve more extensive nerve damage, which takes time to heal.
  • Type of Treatment: The method of treatment can impact recovery time. Injections and high-dose supplements may lead to quicker improvements compared to dietary changes alone.
  • Individual Health Conditions: Underlying health conditions, such as digestive disorders or anemia, can influence how quickly the body responds to treatment. People with additional health issues may experience a slower recovery.

Treatment Options for Vitamin B12 Deficiency

Dietary Changes

Incorporating vitamin B12-rich foods into your diet is an effective way to boost your levels naturally. Here are some foods that are excellent sources of vitamin B12:

Animal Products:

  • Meat: Beef, pork, lamb, and liver
  • Fish: Salmon, trout, tuna, and clams
  • Poultry: Chicken and turkey
  • Dairy: Milk, cheese, and yogurt
  • Eggs

Fortified Foods:

  • Breakfast Cereals: Look for cereals fortified with vitamin B12
  • Plant-Based Milk: Soy, almond, and oat milk fortified with B12
  • Nutritional Yeast: Often fortified with vitamin B12, making it a great addition to vegan and vegetarian diets

Making these foods a regular part of your diet can help prevent deficiency and support overall health.

vitamin b12 foods

Supplements and Injections

If dietary changes are insufficient or not feasible, supplements and injections can effectively manage vitamin B12 deficiency.

  • Oral Supplements: Vitamin B12 tablets are widely available and can be an easy way to increase your intake. They are available separately or as a part of multivitamins.
  • Sublingual Tablets: These tablets dissolve under your tongue, allowing the vitamin to be absorbed directly into the bloodstream, bypassing the digestive system.
  • Injections: For those with severe deficiency or absorption issues, vitamin B12 injections are an effective treatment. These are typically administered by a healthcare provider and can be given once a week initially, then less frequently as levels normalize.
  • Nasal Sprays: A prescription nasal spray can be an alternative for those who prefer not to take pills or injections. This method delivers vitamin B12 directly into the bloodstream through the nasal mucosa.

If you're unsure about your vitamin B12 levels or need personalized recommendations, taking a quiz can help identify potential deficiencies and suggest the right vitamins for you. Take the Docus Quiz to find out which vitamin kit suits your needs.

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Recommended Dietary Allowance from the Institute of Medicine (US) Standing Committee on the Scientific Evaluation of Dietary Reference Intakes and its Panel on Folate data:

Age Male Female Pregnancy LactationLactation
Birth to 6 months* 0.4 mcg 0.4 mcg    
7–12 months* 0.5 mcg 0.5 mcg    
1–3 years 0.9 mcg 0.9 mcg    
4–8 years 1.2 mcg 1.2 mcg    
9–13 years 1.8 mcg 1.8 mcg    
14–18 years 2.4 mcg 2.4 mcg 2.6 mcg 2.8 mcg
19+ years 2.4 mcg 2.4 mcg 2.6 mcg 2.8 mcg
  • * Adequate Intake (AI)

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Vitamin B12 deficiency is a common issue that can significantly impact your health if not addressed promptly. Recovery typically takes a few months to a year, depending on the severity of the deficiency and the effectiveness of the treatment. Early diagnosis and consistent management are crucial for a swift recovery and long-term health.

Incorporating vitamin B12-rich foods into your diet, taking spplements or receiving injections, and regular monitoring can help maintain adequate vitamin B12 levels. 

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