Signs of vitamin B deficiency

Different B vitamins support blood formation, nerve function, and energy metabolism. A deficiency may therefore cause tiredness, pale skin, dizziness, or generalised weakness. Vitamin B12 deficiency can also cause tingling, reduced sensation, balance difficulty, a sore or smooth tongue, and memory or concentration problems. These symptoms can develop gradually and may be mistaken for stress or lack of sleep.

Symptoms do not identify which vitamin is low. Anaemia, coeliac disease, dietary restriction, absorption problems, and some medicines can be relevant. A blood test and a review of diet, medicines, and health history help guide the next step.

Arrange a medical appointment if symptoms persist, recur, or include numbness, balance changes, or thinking difficulties. Do not rely on high-dose supplements to diagnose the cause; they can alter test results or be unsuitable for some people. Bring a list of medicines and supplements, describe your usual diet, and mention any digestive symptoms or previous anaemia.

Seek urgent help for sudden weakness on one side, new trouble speaking, severe breathlessness, fainting, chest pain, or rapidly worsening confusion. Prompt assessment is also sensible for new difficulty walking or spreading numbness, because nerve symptoms may need treatment even when they are not painful.

Ask which blood tests are appropriate, whether your symptoms could reflect anaemia or vitamin B12 deficiency, and whether coeliac disease or absorption problems should be considered. Ask when results will be reviewed and which symptoms should lead you to return sooner.