You keep getting low B12 because of poor absorption (stomach issues, digestive diseases like Crohn's/celiac, surgery, lack of intrinsic factor in pernicious anemia, certain meds) or inadequate intake, especially on vegan/vegetarian diets, as the body can't make it and stores deplete over time. Conditions affecting the stomach lining (gastritis), alcohol use disorder, and aging also hinder absorption, requiring medical investigation to find the specific cause, notes this YouTube video and the NHS.
Diet. Some people can develop a vitamin B12 deficiency as a result of not getting enough vitamin B12 from their diet. A diet that includes meat, fish and dairy products usually provides enough vitamin B12, but people who do not regularly eat these foods can become deficient.
Causes of Vitamin B12 deficiency
Vitamin B12 deficiency can also cause symptoms that affect your brain and nervous system (neurological symptoms), including: numbness. muscle weakness. psychological problems, which can range from mild depression or anxiety, to confusion and dementia.
Key points about vitamin B12 deficiency anemia
Symptoms include weak muscles, numbness, trouble walking, nausea, weight loss, irritability, fatigue, and increased heart rate. Treatment may include vitamin B12 supplements. It is also important to eat a well-balanced diet.
B12 deficiency can trigger specific food cravings, most notably for meat, fish, or eggs, as the body seeks animal-based sources to replenish the vitamin, especially in those on vegetarian/vegan diets or older adults. While cravings for sugary or salty foods can also signal general B-vitamin issues, the distinct urge for protein-rich animal products is a key indicator, but professional testing is crucial for confirmation.
B12 deficiency. Delay in diagnosis and treatment resulted in a near fatal presentation of a common disease. The primary care physician should be aware that there is a window of opportunity for diagnosis and treatment; several complications of Vit. B12 deficiency are irreversible if early treatment is not provided.
Summary: As summarized in the table provided, vitamin B12 (cobalamin) absorption and utilization by the body can be compromised with the chronic use of certain medications which include: colchicine, chloramphenicol, ethanol, histamine 2 receptor antagonists (H2RA), metformin, and proton pump inhibitors (PPI).
Not diet-related
If your vitamin B12 deficiency is not caused by a lack of vitamin B12 in your diet, you'll usually need to have an injection of hydroxocobalamin every 2 to 3 months for the rest of your life.
Severe vitamin B deficiency can cause diseases such as beriberi or pellagra. People who are vitamin B deficient may feel tired, numbness or weakness, among other symptoms.
Underlying medical conditions
Some medical conditions can interfere with how your body processes B12. Those are usually conditions that affect your liver, kidneys or your blood itself. Some examples include: Liver disease and liver failure.
Since your body doesn't make vitamin B12, you have to get it from the foods you eat or from supplements. You can get vitamin B12 deficiency if you can't absorb vitamin B12 due to problems with your gut or if you have pernicious anemia, which makes it difficult to absorb vitamin B12 from your intestines.
Some symptoms related to B12 deficiency are also common in other conditions, as well as from lifestyle factors such as stress, poor sleep and diet. Therefore your GP may want to explore this with you before testing your B12 levels or suggesting treatment.
The following can cause low levels of vitamin B-12:
In fact, some studies have even suggested the opposite. For instance, one study noted that individuals who regularly took vitamin B12 supplements gained between 2.5 to 17 fewer pounds (1.2 to 7.7 kg) over a decade than those who didn't supplement.
Metformin is considered a first-line treatment for adult-onset (Type II) diabetes. However, metformin can cause malabsorption of Vitamin B-12. This is thought to be due to a decrease in bile acid secretion resulting in bacterial overgrowth that causes decreased intestinal absorption.
Complications of vitamin B12 deficiency
The foods highest in Vitamin B12 are animal products, with clams and liver (beef, lamb) being exceptionally rich sources, often providing several hundred percent of the daily value in a single serving, alongside seafood like mussels, sardines, and salmon, dairy, eggs, and fortified cereals and nutritional yeast for vegans.
Particularly, individuals with lung, stomach, colon, oesophageal, and pancreatic cancers are more prone to experiencing a deficiency in vitamin B12. This article will discuss different types of cancers causing vitamin B12 deficiency, associated symptoms, and available treatment options.
For the patients with a very low serum B12 level (<100ng/l) and anaemia, macrocytosis or neurological symptoms, the treatment is simple: load the patient with vitamin B12 parenterally (by IM injection) and continue with maintenance vitamin B12 by IM injection every 3 months indefinitely (see below for more details).
People with very low vitamin B-12 levels can have symptoms such as fatigue, muscle weakness, stomach problems, nerve damage, vision problems and mood changes. They also may have low iron, called anemia, or low blood counts. The recommended daily amount of vitamin B-12 for adults is 2.4 micrograms (mcg).
Cutaneous manifestations associated with vitamin B12 deficiency are skin hyperpigmentation, vitiligo, angular stomatitis, and hair changes. A diagnosis of vitamin B12 deficiency is often overlooked in its early stages because these signs are not specific to vitamin B12 deficiency alone.