Vitamin B12 deficiency can cause serious health issues if left untreated for too long. But how long is too long when it comes to B12 deficiency? Let’s take a closer look at how long the effects of B12 deficiency can last if not properly addressed.
What is Vitamin B12 and Why is it Important?
Vitamin B12 is an essential nutrient that plays many crucial roles in the body. It helps make DNA and produce red blood cells. It’s also important for proper nerve function. Vitamin B12 is found naturally in animal products like meat, eggs, and dairy. It can also be found in fortified foods or taken as a supplement.
When the body doesn’t get enough B12, it can lead to a deficiency. B12 deficiency prevents the body from properly utilizing folic acid and interferes with DNA and red blood cell production. That’s why adequate B12 levels are necessary to make red blood cells and new DNA, and for cells to divide properly.
Causes of B12 Deficiency
There are a few key reasons why someone might become B12 deficient:
- Inadequate intake: This occurs in vegetarians/vegans or older adults who have trouble absorbing B12 from food. Strict vegetarians/vegans are at high risk since B12 is naturally found in animal products.
- Pernicious anemia: This autoimmune condition prevents the body from properly absorbing B12 from foods. It causes about 20% of B12 deficiencies.
- Other health conditions: Issues like celiac disease, Crohn’s disease, bacterial overgrowth in the small intestine, or infection with the tapeworm can also lead to impaired B12 absorption and deficiency.
- Medications: Certain medications like acid reducers and metformin can also deplete B12 levels over time.
In summary, not getting enough B12 through diet or supplements, absorption issues in the digestive tract, health conditions that affect absorption, and certain medications can all contribute to B12 deficiency.
Signs and Symptoms of B12 Deficiency
At first, B12 deficiency may cause no symptoms. But over time, it can lead to serious problems. Here are some common signs of B12 deficiency:
- Fatigue and weakness – One of the earliest signs is feeling extremely tired and weak.
- Pins and needles sensations – Many people report a pins and needles feeling or numbness in their hands and feet.
- Pale skin – A decrease in new red blood cells can lead to unusual paleness.
- Sore tongue – A red, sore tongue is commonly seen with B12 deficiency.
- Appetite changes – You may feel less hungry or even lose your appetite entirely.
- Constipation and diarrhea – Digestive upset is another common symptom.
- Shortness of breath – B12 deficiency can cause shortness of breath and fatigue, even with minimal activity.
- Vision changes – Blurry vision or eye twitching may occur as well.
- Depression and confusion – Many people with B12 deficiency experience depression, memory loss, disorientation, and even dementia-like symptoms.
Symptoms often start gradually. At first they may be mild, come and go, and be overlooked. But if the deficiency continues over months and years, symptoms can become disabling.
Stages of B12 Deficiency
Doctors break vitamin B12 deficiency into several stages:
Stage 1: Depletion
This early stage occurs when your B12 levels start to run low but aren’t yet critically deficient. Since the body stores several years worth of B12, you have ample reserves even though your intake/absorption has decreased. No symptoms are usually present at this point.
Stage 2: Deficient
If inadequate B12 continues, you’ll become truly deficient as liver stores are used up. At this point blood levels will show low B12. Some mild symptoms like fatigue often emerge.
Stage 3: Negative Balance
This is when serious clinical signs and symptoms of deficiency appear. The nerves start to degenerate from lack of B12. Neurological problems like pins and needles, trouble walking, dementia, and vision changes occur. Deficiency symptoms will worsen without treatment.
Stage 4: Severe Deficiency
This advanced stage is when deficiency has gone on for a prolonged period. Severe anemia may develop, along with major neurological issues, nerve damage, psychoses, and impaired brain function. At this point, some of the effects could become irreversible even with treatment.
As you can see, the longer B12 deficiency persists, the worse symptoms become. Treatment in the early stages before major damage occurs is crucial.
How Long Before B12 Deficiency Symptoms Appear?
How long it takes for B12 deficiency symptoms to appear depends on your body’s stores of the vitamin when depletion began. Here’s a breakdown:
- No stores: Synthetic B12 injected directly into the bloodstream will start to become deficient in 1-2 months without ongoing intake.
- Normal B12 stores: People with healthy reserves may not have symptoms for 3-5 years or longer once intake/absorption drops.
- Pernicious anemia: Symptoms may develop within 1-3 years since stores are rapidly depleted when new B12 can’t be absorbed properly.
In most people, it takes around 3-5 years from when B12 absorption issues or inadequate intake begins until deficiency symptoms emerge. But in those with impaired B12 metabolism like pernicious anemia, it happens faster. Symptoms may never appear at all in some with robust stores.
Long-Term Effects of Prolonged B12 Deficiency
If low B12 levels go untreated for years, it can cause permanent impairment. Some effects like vision loss may be reversible with early treatment. But if nerve damage is extensive, some symptoms could become permanent.
Here are some long-term effects of prolonged, severe B12 deficiency:
- Permanent nerve damage – Numbness and tingling that starts in the feet and moves up the legs.
- Difficulty walking and movement – Poor balance and coordination may not improve with treatment later.
- Cognitive problems – Severe deficiency can cause long-term dementia, memory loss, disorientation, and vision loss.
- Spinal cord degeneration – The protective myelin sheath around nerves can be damaged.
- Congestive heart failure – Untreated B12 deficiency can lead to fluid around the heart.
- Birth defects – Pregnant women with severe deficiency may have a higher risk of delivering infants with neural tube defects.
The takeaway is that the longer B12 deficiency goes untreated, the higher the likelihood of permanent effects. Seeking treatment in the early stages is critical.
When to See a Doctor
It’s important not to ignore potential symptoms and prolong deficiency. Contact your doctor promptly if you have any recurring signs of low B12. Children and infants showing impairment should be evaluated right away since they have less B12 reserves.
Testing for B12 deficiency is a simple blood test. Make sure your doctor orders the full panel including serum B12, homocysteine, and methylmalonic acid (MMA) for the most accurate results.
You should also see a doctor if you have any health conditions or take medications that could deplete B12 levels. Routine testing may be advised to check if supplementation is needed.
Treatment for B12 Deficiency
Treating vitamin B12 deficiency as early as possible is crucial. Here are the main treatment approaches:
B12 Injections
Vitamin B12 injections are most commonly used, especially in those with absorption issues. The shots allow B12 to directly enter the blood without going through the digestive tract. Injections are usually given once per month until deficiency is reversed, then once every few months for maintenance.
High-Dose Oral Supplements
Oral B12 supplements in very high doses like 1000-2000 mcg per day may also be used. This floods the body with B12 in hopes that some will make it through damaged areas of the digestive tract and correct the deficiency over time.
Sublingual B12
Sublingual B12 supplements under the tongue are another option that help some people absorb B12 better than traditional oral pills. The B12 is absorbed directly into the bloodstream through the tissue under the tongue.
Improved Diet
If deficiency was caused by inadequate B12 intake rather than absorption issues, a diet change with B12-rich foods or standard low-dose supplements may resolve it. Nutritional yeast, beef liver, salmon, eggs, dairy and fortified foods can prevent reoccurrence.
Treat Underlying Conditions
It’s also important to diagnose and treat any health problems causing B12 malabsorption, like celiac or Crohn’s disease. This may allow normal absorption to resume.
Recovery Time for B12 Deficiency
How long it takes to recover from B12 deficiency depends on factors like:
- How long you’ve been deficient
- Severity of the deficiency
- Type of treatment used
- Whether you have pernicious anemia
- Your adherence to treatment
Those treated in the early deficiency stages through diet or supplements typically start feeling better within weeks as B12 levels rebound. Any related fatigue, appetite changes, and digestion issues may improve within days to months with replenishment.
However, recovery takes longer the more advanced the deficiency. Nerve damage can require 6-12 months for significant healing, though some symptoms persist. Pernicious anemia may have a prolonged response time. Careful adherence to lifelong treatment is essential.
How to Prevent B12 Deficiency
The key ways to prevent vitamin B12 deficiency include:
- Eat B12-rich foods like meat, seafood, eggs, and dairy products. Fortified grains and cereals contain B12 as well.
- Take B12 supplements if at risk for deficiency – especially critical for vegans/vegetarians.
- Get checked for absorption issues if deficient, and treat any underlying conditions.
- Discuss medications that could deplete B12 with your doctor.
- Get bloodwork periodically if at high risk for deficiency.
Ensuring adequate intake through diet and/or supplementation is most important. Those with increased risk due to medical conditions should be vigilant about prevention and testing.
Key Takeaways
- B12 deficiency symptoms may take 3-5 years to develop in healthy people with robust stores. In those with impaired absorption like pernicious anemia, it can happen within 1-3 years.
- Prolonged and severe deficiency can cause permanent effects like nerve damage, vision loss, and cognitive decline.
- See a doctor promptly if you have fatigue, tingling, anemia, memory changes, or risk factors. Don’t delay treatment.
- Injections, high oral doses, and sublingual supplements can all treat deficiency. Diet changes and treating underlying conditions may also help.
- Recovery time depends on the severity and cause. Nerve damage may take over 6 months to improve. Preventing deficiency is ideal.
The Bottom Line
B12 deficiency often develops slowly over years before symptoms emerge. But the longer someone has low B12, the higher the risks of permanent neurological and cognitive damage. Seeking treatment in the early stages is crucial. Anyone with deficiency symptoms or risk factors should have B12 levels tested promptly and start treatment if warranted.
With an adequate diet, supplements if needed, and properly addressing any absorption issues, most cases of B12 deficiency can be corrected fully or managed successfully. This helps avoid the potentially debilitating effects of prolonged severe deficiency.