Vitamin B12 deficiency is often overlooked because its symptoms can develop slowly and may resemble other health problems. Untreated deficiency can affect the blood, nerves, and brain, so recognizing warning signs is important.
Common signs of vitamin B12 deficiency that are often ignored
- Persistent tiredness and weakness
- Feeling unusually fatigued, low on energy, or physically weak can occur because B12 is needed to make healthy red blood cells.
- Tingling or numbness in the hands and feet
- A “pins and needles” sensation, burning feeling, or reduced sensation may happen when low B12 affects nerves.
- Balance problems or difficulty walking
- Nerve damage from prolonged deficiency can affect coordination and stability.
- Memory problems or trouble concentrating
- Some people experience brain fog, forgetfulness, or difficulty focusing.
- Mood changes
- Low B12 levels have been associated with irritability, low mood, and symptoms that may resemble depression.
- Pale or yellowish skin
- A deficiency can cause anemia, which may make skin look pale; in some cases, changes in red blood cells can contribute to a yellowish appearance.
- Sore or swollen tongue
- A smooth, red, painful tongue (sometimes called glossitis) can be a sign of B12 deficiency.
- Shortness of breath or dizziness
- If anemia develops, reduced oxygen delivery can cause breathlessness, lightheadedness, or a racing heartbeat.
- Vision changes
- Rarely, B12 deficiency can affect the optic nerve and contribute to vision problems.
- Unusual sensations or sensitivity
- Some people notice increased sensitivity to touch, difficulty sensing temperature, or discomfort from normal sensations.
Who is more likely to have low B12?
- Older adults
- People following a strict vegan diet without B12 supplementation
- People with absorption problems (such as certain stomach or intestinal disorders)
- People who have had stomach or intestinal surgery
- Those taking certain medications that can affect B12 absorption (such as long-term metformin or acid-reducing medicines)
A blood test can help check B12 status, and treatment depends on the cause and severity (for example, dietary changes, oral supplements, or injections). If symptoms like numbness, balance problems, or cognitive changes are present, it’s worth discussing them with a healthcare professional because nerve effects can become harder to reverse if deficiency continues for a long time.
