Pernicious Anemia in a Vegan Diet: A Case of Vitamin B12 Deficiency and its Neurological Implications

Dorota Slokar^*
*Correspondence: Dorota Slokar, Department of Biochemistry, Catholic University of Uruguay, Montevideo, Uruguay, Email:

Introduction

Pernicious anemia, a condition often linked to vitamin B12 deficiency, is a growing concern within various dietary groups, particularly among individuals following vegan diets. Vitamin B12, a water-soluble vitamin crucial for red blood cell formation, neurological function and DNA synthesis, is primarily found in animal-based foods. As a result, those who adopt a vegan lifestyle avoiding all animal-derived products are at risk of insufficient B12 intake, potentially leading to deficiencies. This condition can have serious neurological and hematological consequences if left unaddressed, manifesting in symptoms ranging from fatigue and weakness to severe cognitive and motor dysfunction. The rising popularity of vegan diets, driven by ethical, environmental and health considerations, necessitates a thorough understanding of their potential nutritional implications. While often associated with numerous health benefits, a strict vegan diet inherently excludes all animal products, the primary dietary sources of vitamin B12 (cobalamin). This essential nutrient plays a crucial role in various physiological processes, most notably in red blood cell formation and the maintenance of a healthy nervous system. Consequently, individuals adhering to a long-term, unsupplemented vegan diet are at significant risk of developing vitamin B12 deficiency [1].

Description

Pernicious anemia is a type of megaloblastic anemia caused by a deficiency in vitamin B12, which plays a vital role in the production of healthy red blood cells, nerve function and DNA synthesis. When vitamin B12 levels are inadequate, the body cannot produce enough red blood cells, leading to anemia and the lack of B12 can also severely affect the nervous system. The primary cause of pernicious anemia is an autoimmune disorder that inhibits the absorption of B12 in the intestines. However, in the case of individuals following a vegan diet, the deficiency is most often due to an insufficient intake of vitamin B12, as it is predominantly found in animal-derived foods like meat, fish, dairy and eggs. A vegan diet, while beneficial in many aspects, inherently lacks natural sources of vitamin B12. Without careful attention to supplementation or consumption of B12-fortified foods, vegans are at risk of developing a deficiency. Vitamin B12 deficiency, if not addressed, can lead to a wide array of symptoms that impact various systems in the body. Neurologically, the lack of B12 can cause irreversible damage to the central and peripheral nervous systems. Common neurological symptoms include numbness or tingling in the hands and feet, difficulty walking, memory problems and even mood disturbances such as depression or cognitive decline [2].

In some cases, neurological impairment due to B12 deficiency can be severe and permanent, underscoring the importance of early detection and treatment. One of the challenges in diagnosing B12 deficiency, particularly in individuals on vegan diets, is that the early symptoms such as fatigue and weakness are often attributed to other conditions or lifestyle factors. As the deficiency progresses, more specific symptoms like neuropathy or cognitive dysfunction may emerge, but by this time, the damage to the nervous system may already be significant. This case study aims to highlight the importance of recognizing B12 deficiency in vegans, particularly as neurological symptoms can develop insidiously and may not be immediately linked to the underlying cause. Treatment typically involves vitamin B12 supplementation, either through oral tablets or injections, which can restore B12 levels and reverse some of the hematological and neurological impairments if caught early. However, if the deficiency has been longstanding and neurological damage has already occurred, the effects may be partially or fully irreversible. Thus, this paper stresses the need for a balanced and informed approach to vegan diets, including regular monitoring of vitamin B12 levels and proactive supplementation [3].

For individuals following a vegan diet, the challenge lies not only in ensuring adequate B12 intake but also in understanding the forms of vitamin B12 that are most effective for absorption. While some plant-based foods contain compounds that mimic B12, such as certain types of algae or fermented foods, these forms are often not biologically active or are poorly absorbed by the body. As a result, vegans must rely on fortified foods or B12 supplements to meet their nutritional needs. Common sources of B12 fortification include plant-based milk, breakfast cereals, nutritional yeast and certain meat substitutes. Regular consumption of these fortified foods, or the use of a daily B12 supplement, is essential to prevent deficiency and its associated risks. The neurological implications of vitamin B12 deficiency are particularly concerning. The nervous system requires B12 for the synthesis of myelin, the protective sheath surrounding nerve fibers that ensures proper nerve signal transmission. When B12 levels drop, myelin production is impaired, leading to demyelination, this can cause irreversible nerve damage [4].

Symptoms such as peripheral neuropathy, characterized by tingling or numbness in the hands and feet, are common in individuals with prolonged B12 deficiency. In severe cases, individuals may experience difficulty with coordination, walking and balance, a condition known as ataxia. Cognitive symptoms like memory loss, confusion and even dementia can also occur, further underscoring the need for vigilant monitoring and early intervention in those at risk. While the neurological damage from vitamin B12 deficiency can be significant, it is important to note that the body can often recover with appropriate treatment, especially if B12 deficiency is detected early. In many cases, supplementation with B12 can reverse hematological symptoms like anemia and improve energy levels within a few weeks. Neurological recovery, however, is more complex. The extent of recovery depends on the duration and severity of the deficiency before treatment began. If the neurological damage is severe or longstanding, full recovery may not be possible, highlighting the critical importance of preventing deficiency in the first place. This is especially crucial for those following vegan diets, as they may be unaware of the risks associated with B12 deficiency and the need for regular monitoring and supplementation [5].

Conclsuion

In conclusion, vitamin B12 deficiency, particularly in individuals following a vegan diet, presents significant risks, especially concerning neurological health. Pernicious anemia, a direct result of B12 deficiency, can lead to severe and sometimes irreversible nerve damage if not detected and treated promptly. While a vegan diet can be healthful, it requires careful planning to ensure adequate B12 intake, either through fortified foods or supplements. Early detection and proactive management are essential to preventing both hematological and neurological complications. Ultimately, raising awareness about the importance of B12 supplementation and regular monitoring is key to safeguarding the health of those on plant-based diets.

Acknowledgment

None.

Conflict of Interest

None.

References

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