Vitamin B12 is a crucial nutrient for keeping your nerve and blood cells healthy. It also helps in the formation of DNA, the genetic material present in all cells of the body.

Vitamin B12, like all B vitamins, is water-soluble, which means that the body does not store it. This also means that people need to have an adequate daily intake to prevent a deficiency or low vitamin B12 levels.

Vitamin B12 deficiency can lead to an array of health complications, including pernicious anemia, neurological problems, and even cognitive decline.

If you’re feeling fatigued or weak, notice that your skin is becoming pale or yellowish, or that you are experiencing numbness or tingling in your hands or feet, there could be a possibility that you are not getting enough vitamin B12.

What Causes Low Vitamin B12 Levels?

Now, let’s look at some of the most common underlying causes of low vitamin B12 levels:.

Lack of Vitamin B12 in Diet

The human body does not make vitamin B12. Therefore, it’s important to consume this vitamin through food or supplements. Vitamin B12 is mainly found in animal products, such as meat, fish, poultry, eggs, and dairy products.

For vegans and vegetarians, they would need to eat specific fortified foods or take B12 supplements regularly. If you do not eat enough of these foods, the lack of dietary intake will cause low vitamin B12 levels.

Intestinal Malabsorption

The stomach produces a protein known as intrinsic factor, which combines with vitamin B12 in the small intestine and helps in its absorption. Intrinsic factor is secreted by the parietal cells in the stomach.

In some cases, autoimmune diseases or atrophic gastritis can inflame these cells, causing a deficiency of intrinsic factor production. Without intrinsic factor, the body cannot absorb vitamin B12 adequately, leading to low vitamin B12 levels.

Other health conditions may also cause malabsorption. Celiac disease, for example, is an autoimmune disorder in which the immune system attacks the small intestine, inflaming and damaging the lining that is responsible for nutrient absorption.

People with celiac disease are also at risk of low vitamin B12 levels. Gastric bypass surgery can also lead to malabsorption of vitamin B12, as post-surgery, the body may not produce enough intrinsic factor needed for its absorption.

Disorder of the Small Intestine

Diseases or disorders of the small intestine can also interfere with the absorption of vitamin B12 from the food we eat. Crohn’s disease, for instance, is an inflammatory bowel disease that causes inflammation of parts of the digestive tract.

It can also lead to damage to the intestinal wall that can interfere with vitamin B12 absorption. Other conditions that can contribute to low vitamin B12 levels by damaging the small intestine include irritable bowel syndrome, bacterial overgrowth, and diverticulitis.

Alcoholism

Excessive alcohol consumption, for a long period, can increase the risk of low vitamin B12 levels.

Alcoholism can cause inflammation in the stomach lining, leading to damage to the cells that produce intrinsic factor, resulting in the decreased absorption of the vitamin. Additionally, alcohol abuse can interfere with the breakdown and absorption of nutrients needed for the production of intrinsic factor, further contributing to the development of low vitamin B12 levels.

Pernicious Anemia

Pernicious anemia is an autoimmune condition caused by the destruction of gastric parietal cells. This destruction leads to the insufficient production of intrinsic factor, leading to anemia.

When the body does not produce enough intrinsic factor, it can’t absorb vitamin B12 properly, leading to low vitamin B12 levels. People with pernicious anemia typically require regular vitamin B12 injections to help manage the condition and prevent complications.

Age Factor

Sometimes, low vitamin B12 levels can be a product of aging.

This is because, as we get older, our digestive system’s efficiency decreases; specifically, the stomach produces less acid and intrinsic factor, and the small intestine is less able to absorb vitamin B12. As a result, older people can develop low vitamin B12 levels, even if they consume adequate amounts of the vitamin.

Medications

Long-term use of certain medications may contribute to low vitamin B12 levels. For instance, proton pump inhibitors used to treat acid reflux may reduce gastric acid production, which can impact intrinsic factor production and vitamin absorption.

Metformin, a commonly used medication for diabetes, may also lead to vitamin B12 deficiency, as it interferes with the absorption of the vitamin from the diet.

Genetics

In rare instances, some genetics disorders can affect intrinsic factor production or interfere with vitamin B12 absorption, resulting in low vitamin B12 levels.

For instance, if a genetic defect is present in DNA synthesis, it can hamper vitamin B12 metabolism. Other rare genetic disorders associated with low vitamin B12 levels include Imerslund-Gräsbeck syndrome and transcobalamin II deficiency.

Conclusion

If you’re experiencing fatigue, weakness, or any of the symptoms related to low vitamin B12 levels, it’s important to talk to your healthcare provider and seek professional advice.

While the underlying reasons for low vitamin B12 levels can vary, a proper diagnosis and treatment plan can help manage the symptoms and prevent complications associated with low vitamin B12 levels.