Vitamin B12 deficiency may explain persistent exhaustion

A Mirror report says a routine blood test found a vitamin B12 (or folate) deficiency after prolonged tiredness, with the writer’s ulcerative colitis likely contributing; experts in the article describe fatigue and neurological symptoms as common signs and note multiple causes including diet, absorption problems and some medications.

Many people shrug off ongoing tiredness as a result of late nights, weather or low activity. In this article the author describes being persistently exhausted until a routine blood test revealed a vitamin B12 or folate deficiency. The author’s ulcerative colitis was reported as a likely factor because it limited diet and nutrient absorption. Medical experts quoted in the piece describe how B12 issues can present with both physical and neurological symptoms. Key points: - The article reports extreme fatigue is a common and prominent symptom of vitamin B12 deficiency, along with breathlessness, weakness and cognitive changes. - Reported causes include low dietary intake (for example on some plant-based diets without fortified foods), impaired absorption (pernicious anaemia, gut conditions, prior stomach or bariatric surgery), advancing age, certain medications (including metformin and long-term acid-suppressing drugs), alcohol misuse and nitrous oxide exposure. - Typical signs noted in the piece include persistent tiredness, pale or slightly yellow skin, a sore or smooth tongue, mouth ulcers, pins and needles in hands or feet, memory or concentration problems, low mood and balance or nerve issues in longer-standing cases. - Diagnosis is described as requiring blood tests such as a full blood count and serum B12, with active B12, methylmalonic acid or homocysteine checks suggested when results are unclear. - Treatment approaches reported range from oral supplements to high-dose sublingual formulations or regular injections, depending on the underlying cause and absorption ability. - The article cites an analysis that about five million B12 prescriptions (supplements and injections) were issued in the UK in 2024, underscoring how common the issue is reported to be. Summary: The article conveys that low vitamin B12 can underlie persistent exhaustion and a range of neurological or physical symptoms, and that causes may be dietary, related to absorption, or linked to medications or other health conditions. It reports that diagnosis generally involves blood testing and that management options described in the piece include oral supplementation, sublingual preparations or injections depending on the cause.