Understanding the Implications of Low Vitamin B12: Signs, Symptoms, and Solutions

Vitamin B12 is an essential nutrient that your body requires but cannot produce independently. It plays a critical role in maintaining nerve tissue health, brain function, and the production of red blood cells. Despite its importance, vitamin B12 deficiency remains one of the most underdiagnosed nutritional deficiencies worldwide, partly because the medical system's diagnostic ranges are often too low. For a more accurate assessment, serum B12 levels should ideally be above 600 pg/mL and active B12 above 125 pmol/L. This blog will explore the implications of low vitamin B12 levels, highlight the signs and symptoms, explain how to check your B12 status, and discuss effective strategies to boost your intake. 

Signs and Symptoms of Low Vitamin B12

Vitamin B12 deficiency might not show clear symptoms at first, but it can lead to serious complications over time if left untreated. Below is a list of common signs and symptoms to be aware of, though it is by no means exhaustive – click here for a more comprehensive list:

  • Fatigue or Lack of Energy: Feeling unusually tired or lethargic can be one of the first signs of vitamin B12 deficiency.
  • Weakness: Low B12 levels can lead to a feeling of physical weakness or muscle weakness.
  • Pale or Jaundiced Skin: Individuals with B12 deficiency may have a pale appearance or noticeable jaundicing of the skin and eyes due to the lack of red blood cell production.
  • Heart Palpitations and Breathlessness: An inadequate supply of red blood cells can lead to an elevated heart rate and feeling short of breath.
  • Nerve Problems like Numbness or Tingling: Vitamin B12 is crucial for the health of the nervous system and deficiency can cause sensations of pins and needles.
  • Changes in Mobility: In severe cases, the nerve damage caused by low vitamin B12 can affect coordination and balance.
  • Glossitis and Mouth Ulcers: This involves inflammation of the tongue, which becomes swollen and pale, often accompanied by mouth ulcers.
  • Mood Changes: Deficiency in this vitamin can lead to irritability, depression, and cognitive changes.


How to Check Your B12 Levels

When assessing vitamin B12 status, a standard blood test is often the first step. This test measures the concentration of B12 circulating in the bloodstream. However, it's important to understand that serum/Active B12 levels do not always accurately reflect the vitamin's bioavailability or the body's ability to utilize it effectively. This discrepancy can particularly occur if there are absorption issues or genetic factors at play.

A more comprehensive and accurate measure of B12 status is provided by Organic Acid Testing (OAT), which includes checking levels of methylmalonic acid (MMA). Elevated MMA levels can indicate a true B12 deficiency, even when serum/Active B12 levels appear normal. MMA is a byproduct of metabolism that accumulates when B12 is deficient, thus serving as a sensitive marker for detecting early stages of deficiency, particularly at the cellular level where it impacts energy production and DNA synthesis.

Genetic testing play a crucial role in understanding individual susceptibilities to vitamin B12 deficiencies by identifying specific genetic mutations. Mutations in genes such as MTHFR (Methylenetetrahydrofolate Reductase), MTR (Methionine Synthase), MTRR (Methionine Synthase Reductase), and TCN2 (Transcobalamin II) can significantly influence how well your body processes and utilizes vitamin B12. For instance, the MTHFR gene mutation can affect folate metabolism, indirectly impacting B12 function in cellular processes. Similarly, mutations in MTR and MTRR can disrupt the methylation cycle, which is crucial for DNA synthesis and repair, as well as for the proper functioning of the nervous system. The TCN2 gene plays a direct role in B12 transport within the body, and mutations here can lead to deficiencies by impairing the delivery of B12 to the cells where it is needed. Testing for these genetic factors can provide valuable insights, allowing for a tailored approach to nutrition and supplementation that corrects or compensates for these genetic predispositions, thereby improving overall health outcomes.


How to Increase Vitamin B12 Levels

If you are diagnosed with low vitamin B12 levels, here are some effective ways to increase your intake:

Dietary Adjustments: Vitamin B12 is primarily found in animal products, making it a nutrient that requires attention in plant-based diets. Common dietary sources include meat, fish, dairy products, and eggs, which provide the most bioavailable forms of B12. For individuals who follow a vegetarian or vegan lifestyle, obtaining an adequate amount of this essential nutrient can be more challenging since plant foods do not naturally contain vitamin B12.

For vegetarians, some intake can be maintained through the consumption of dairy products and eggs, but vegans must be particularly mindful to include alternative sources of B12 in their diets. Fortified foods play a critical role here; many types of plant-based milks, soy products, breakfast cereals, and nutritional yeast are fortified with B12. These can help fill the nutritional gap, but it's important to check product labels to ensure that these items are indeed fortified with adequate amounts of the vitamin.

Despite these measures, the amount of B12 in fortified foods can vary, and reliance solely on these sources may not suffice for some individuals. Therefore, vitamin B12 supplementation is often recommended for vegans and strict vegetarians. Supplements provide a reliable method of ensuring adequate intake and can be particularly important for those with increased needs, such as pregnant women or the elderly.

While vegetarians might manage to obtain B12 through dairy products and eggs, vegans should seriously consider regular supplementation to prevent deficiency. This is crucial not only for maintaining energy levels and cognitive function but also for long-term health, as B12 is essential for nerve function and the production of DNA and red blood cells. In my practice, I stress the importance of B12 supplementation for vegetarians and vegans and offer guidance on appropriate dosage and type of supplement to best meet individual needs and dietary practices.


Supplementation: B12 supplements are available in various forms, including tablets, capsules, and injections, to cater to different absorption needs and dietary preferences. For individuals with absorption difficulties, injections—such as those of hydroxycobalamin—are particularly effective, as they bypass the digestive system and directly enter the bloodstream. Meanwhile, tablets and capsules, which often contain cyanocobalamin, methylcobalamin, or hydroxycobalamin, are suitable for those on a plant-based diet or for individuals who are low in B12 and need supplementation. Each form of B12 has unique absorption characteristics and uses within the body. For a deeper understanding, be sure to check out our blog on the different forms of vitamin B12 and how each is absorbed.


Addressing Absorption Issues: Enhancing vitamin B12 levels effectively often goes beyond simply increasing dietary intake or supplementing. It's crucial to ensure that the body is capable of absorbing and utilizing the vitamin properly. Various health conditions can impair the absorption of B12, making this an important factor to consider.

One significant condition linked to impaired B12 absorption is pernicious anemia, a form of autoimmune disease where the body lacks intrinsic factor, a protein normally produced by the stomach lining. This protein is essential for the absorption of B12 from the small intestine. Without intrinsic factor, even sufficient dietary B12 cannot be absorbed effectively, leading to deficiency.

Another common absorption barrier is the long-term use of acid-reducing drugs, such as proton pump inhibitors (PPIs) and H2 blockers. These medications, often prescribed for acid reflux or gastroesophageal reflux disease (GERD), reduce stomach acid, which is necessary for releasing B12 from food and preparing it for absorption in the small intestine.

Additionally, various gastrointestinal disorders can also impact B12 absorption. Conditions like celiac disease, Crohn's disease, or surgical removal of parts of the stomach or small intestine can lead to decreased absorption of nutrients, including B12. These conditions may damage or alter the lining of the gut, where B12 absorption takes place, hindering the body’s ability to utilize this crucial nutrient.

For individuals dealing with these issues, it’s essential to address the underlying causes of impaired absorption. This might involve altering medication regimes, treating gastrointestinal diseases, or, in the case of pernicious anemia, bypassing the need for intrinsic factor by using B12 injections. These injections can deliver the nutrient directly into the bloodstream, ensuring that the body receives the B12 it needs without relying on faulty gastrointestinal absorption mechanisms.

Furthermore, Genetic mutations, as mentioned above, in genes such as MTHFR, MTR, MTRR, and especially TCN2 can significantly impact the body's ability to absorb and utilize vitamin B12. The TCN2 gene encodes for transcobalamin II, a protein essential for the transport of vitamin B12 from the intestines to cells throughout the body. Mutations in the TCN2 gene can lead to a functional deficiency of transcobalamin II, thereby hindering the effective delivery of vitamin B12 at the cellular level, despite adequate intake through diet or supplements.


When to Seek Professional Guidance

If you’re experiencing any of the symptoms associated with low vitamin B12, or if you're at risk due to dietary choices or health conditions, professional guidance can be crucial. As a Herbal Naturopath practicing in functional medicine, I focus on identifying the root causes of health issues like B12 deficiency. I use comprehensive testing approaches, including blood work and functional medicine testing, to accurately diagnose and address deficiencies.

Don’t let B12 deficiency go unchecked as it could lead to significant health issues over time. By visiting my practice, you can expect a thorough examination that not only assesses your nutrient levels but also looks at your overall health from a holistic perspective. Together, we can work on a personalized plan that includes diet, supplements, and lifestyle changes tailored to boost your vitamin B12 levels and enhance your overall wellbeing.

Feel free to reach out and schedule a consultation. Let’s ensure your body receives the vital nutrients it needs to function optimally. Remember, in health, every nutrient counts!

 If you are interested in the types of B12 there are available and how your absorb them take a look at our blog on Exploring the Spectrum: Understanding the different types of B12

We also offer free 15 minute phone consultation.

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