Signs of Vitamin B12 Deficiency That Are Often Overlooked

Vitamin B12 is essential for making healthy red blood cells, maintaining the nervous system, and supporting DNA production. A deficiency can develop slowly, and some symptoms may be mistaken for normal ageing, stress, or other health problems.

1. Persistent Tiredness and Weakness

Low B12 can contribute to anaemia, which may cause:

• Ongoing fatigue
• Low energy
• Feeling weak
• Reduced ability to exercise

2. Numbness or Tingling

One of the more important signs is nerve-related symptoms, such as:

• Pins and needles in the hands or feet
• Numbness
• Burning sensations
• Reduced sensitivity to touch

Long-lasting deficiency can sometimes lead to nerve damage.

3. Balance Problems

B12 deficiency can affect nerves involved in movement and coordination, causing:

• Unsteadiness while walking
• Increased risk of falls
• Feeling less coordinated

4. Memory and Concentration Changes

Some people notice:

• Difficulty concentrating
• Forgetfulness
• “Brain fog”
• Slower thinking

These symptoms can have many causes, so testing is often needed to identify the reason.

5. Mood Changes

Low B12 levels have been associated with:

• Low mood
• Irritability
• Anxiety-like symptoms

A deficiency may affect the production and function of chemicals involved in brain health.

6. Pale or Yellowish Skin

B12 deficiency anaemia can cause:

• Pale skin
• A slightly yellow tint to the skin in some cases

7. A Swollen or Sore Tongue

Possible signs include:

• A smooth, red tongue
• Burning or soreness
• Mouth ulcers

8. Shortness of Breath or Dizziness

If anaemia develops, the body may struggle to carry enough oxygen, leading to:

• Breathlessness with activity
• Light-headedness
• Fast heartbeat

9. Vision Changes

Rarely, severe or prolonged B12 deficiency can affect the optic nerve and cause vision problems.

10. Digestive Symptoms

Some people experience:

• Loss of appetite
• Constipation
• Diarrhoea
• Unexplained weight loss

Who Is More at Risk of B12 Deficiency?

Higher risk groups include:

• Older adults
• People who follow a strict vegan diet
• People with conditions affecting absorption (such as pernicious anaemia or certain digestive disorders)
• People who have had some stomach or bowel surgeries
• Those taking certain long-term medications, including some acid-reducing medicines or Metformin

How Is B12 Deficiency Diagnosed?

A healthcare professional may check:

• Vitamin B12 blood levels
• Complete blood count (to look for anaemia)
• Other markers of B12 status if needed

When to Seek Medical Advice

Speak with a healthcare professional if you have:

• Persistent numbness or tingling
• Balance problems
• Unexplained fatigue
• Memory changes
• Symptoms of anaemia

Early diagnosis matters because nerve symptoms may become harder to reverse if a severe deficiency is left untreated for a long time.

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