Feeling low on B12 usually stems from your diet (especially vegan/vegetarian), poor absorption due to stomach/intestinal issues (like pernicious anemia, Crohn's, surgery) or medications, heavy alcohol use, or increased body needs, impacting nerve function, energy, and mood, often showing as fatigue, tingling, or a sore tongue.
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.
feeling weak or tired. diarrhoea. a sore or red tongue, sometimes with mouth ulcers. problems with memory, understanding and judgment (cognitive changes)
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.
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.
Vitamin B12 deficiency anaemia is usually treated with injections of vitamin B12, called hydroxocobalamin. At first, you'll have these injections every other day for 2 weeks or until your symptoms have started improving. Your GP or nurse will give the injections.
Low vitamin B12 can cause fatigue, weakness, nerve issues like numbness and tingling, memory problems, mood changes (depression/anxiety), pale skin, and digestive upset, as it's vital for healthy blood cells and nerves; if untreated, severe deficiency can lead to anemia and serious neurological damage.
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.
Disturbed or blurred vision can also occur as a result of a Vitamin B12 deficiency. This happens when the deficiency causes damage to the optic nerve that leads to your eyes. The nervous signal that travels from the eye to the brain is disturbed due to this damage, leading to impaired vision.
Two common types of GERD medicines have been linked to vitamin B-12 deficiency:
The connection between insufficient vitamin B12 and cancer is complex and multifaceted. Research suggests that vitamin B12 deficiency increases the risk of certain types of cancer, including stomach cancer, breast cancer and colorectal cancer.
What causes vitamin B12–deficiency anemia?
The following groups are among those most likely to be vitamin B12 deficient.
Symptoms of vitamin B12 or folate deficiency anaemia
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.
Causes 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.
Hydroxocobalamin starts to work straight away. However, it may take a few days or weeks before your vitamin B12 levels and symptoms (such as extreme tiredness or lack of energy) start to improve.
Tuna is an excellent source of vitamin B12, an essential vitamin needed to make DNA. Vitamin B12 also helps you to form new red blood cells and prevent the development of anemia.
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.