If a vitamin B12 deficiency stays low and is left untreated, it can lead to severe and potentially irreversible damage to your nervous system and blood, including permanent nerve damage and heart conditions.
Key points about vitamin B12 deficiency anemia
Without enough red blood cells, your tissues and organs don't get enough oxygen. Without enough oxygen, your body can't work as well. Symptoms include weak muscles, numbness, trouble walking, nausea, weight loss, irritability, fatigue, and increased heart rate.
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.
If you have vitamin B12–deficiency anemia, you may have the typical symptoms of anemia at first, such as fatigue, paleness, shortness of breath, headaches, or dizziness. If left untreated, you may start to notice brain and nervous system symptoms.
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.
Stage 1 is decreased levels of vitamin B12 in the blood. Stage 2 is low concentration of vitamin B12 in the cell and metabolic abnormalities. Stage 3 is increased levels of homocysteine and MMA and decreased DNA synthesis resulting in neuropsychiatric symptoms. Stage 4 is macrocytic anemia.
Stomach acid helps to release vitamin B12 from foods. Older people have reduced stomach acid. People that take medication that suppresses stomach acid for conditions like peptic ulcer disease or gastroesophageal reflux disease (GORD) can have difficulty absorbing vitamin B12 from food.
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.
Vitamin B12 shots are often recommended to boost energy, improve mood, and support overall health. For many, they work wonders. But for some, the experience can be confusing.. Feeling worse after a B12 shot often reflects an initial “healing crisis” as your body repairs cells and releases stored toxins.
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.
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).
Disturbed or blurred vision can also occur as a result of a Vitamin B12 deficiency.
If your deficit is mild, you may respond quickly to medication and eating more foods containing B12. If you have chronic low B12 levels or have underlying health conditions that cause the deficiency, you may need to take B12 for the rest of your life (or for as long as you have the underlying condition).
Lower B12 correlates with slower processing speeds, brain lesions. In the study, researchers enrolled 231 healthy participants without dementia or mild cognitive impairment, whose average age was 71. They were recruited through the Brain Aging Network for Cognitive Health (BrANCH) study at UCSF.
People need vitamin B-12 for the brain to work well. If not treated, vitamin B-12 deficiency can lead to issues with the nerves, brain or spinal cord. These might include lasting tingling in the hands and feet or trouble with balance.
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.
The best form of B12 is often considered methylcobalamin, as it's a naturally occurring, active form the body uses immediately, though adenosylcobalamin is also an active form, with a combination often recommended for better results, especially for deficiency or absorption issues, while cyanocobalamin, a cheaper synthetic option, is effective but requires conversion and is less ideal for some. For general supplementation, natural forms like methylcobalamin or adenosylcobalamin are preferred for better retention.
Vitamin B12 level
The clinically normal level for cobalamin is unclear, although it is thought that serum cobalamin of less than 200 nanograms/L (148 picomol/L) is sensitive enough to diagnose 97% of people with vitamin B12 deficiency.
Typically, our patients experience positive effects between 24-72 hours after the treatment. People with severe deficiencies may require a few injections to start feeling the benefits and will be overseen by a medical professional to ensure accurate dosage to optimise results.
Causes of Vitamin B12 deficiency
Symptoms of vitamin B12 or folate deficiency anaemia
Vitamin B12 is essential for nerve cell health and a deficiency can lead to nerve damage. This damage can in turn cause itching by disrupting the nerve signals in the skin. Another factor that may play a role in itching due to vitamin B12 deficiency is the influence of vitamin B12 on the immune system.
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.