Overview
- NHS guidance says cognitive changes can accompany fatigue, pins and needles, muscle weakness and a sore, inflamed tongue.
- GP Dr Suraj Kukadia used TikTok to note that B12 deficiency symptoms are often non‑specific and to encourage medical assessment.
- Pernicious anaemia is identified as the most common cause because it blocks B12 absorption, while low intake risks rise for people avoiding animal products.
- These deficiencies are diagnosed with blood tests and typically treated with B12 injections or tablets, sometimes continuing long term depending on cause.
- NHS figures estimate around 6% of people under 60 and 20% over 60 are affected, vegans face additional risk, and up to 2 mg of supplemental B12 daily is considered unlikely to cause harm.