A simple reference guide for symptoms that may need further investigation
If you have been told you are anaemic, or you are worried about tiredness, weakness, breathlessness, dizziness or abnormal blood results, you can book a careful GP-led assessment with me, Dr Asim Naqvi, to help you understand what may be going on.
All Signs
Signs are things that may be noticed during a clinical assessment or identified through blood tests. They can provide useful clues, but they need to be interpreted alongside your symptoms, medical history and risk factors.
Abnormal thyroid results
Thyroid problems can cause overlapping symptoms, so testing may be useful when the cause is unclear.
Altered sensation
Reduced sensation, numbness or abnormal nerve findings may be identified during a focused neurological assessment.
Anaemia
Anaemia means haemoglobin or red blood cells are low, which can contribute to tiredness, breathlessness and weakness.
Balance changes
Unsteadiness, altered walking or coordination changes may suggest nerve involvement and should be assessed carefully.
Borderline B12
A borderline B12 result may still matter, especially if symptoms, risk factors or previous treatment complicate the picture.
Enlarged red blood cells
B12 or folate deficiency may cause enlarged red blood cells, although this change is not always present.
Fast heartbeat
A fast heartbeat may be noticed during examination and can occur with anaemia or other medical conditions.
Low B12
A blood test may show low vitamin B12, which needs interpreting alongside symptoms, risk factors and supplement use.
Low ferritin
Low ferritin can suggest reduced iron stores, sometimes before anaemia is clearly visible on a full blood count.
Low iron markers
Iron studies may show reduced iron availability, which can help assess iron deficiency and related anaemia.
Mouth changes
Mouth ulcers, soreness or visible tongue changes may appear alongside other symptoms of B12 or folate deficiency.
Pale skin
Pale skin can be seen with anaemia or iron deficiency, although it varies and is not diagnostic alone.
Red or sore tongue
A red, sore or inflamed tongue can occur with B12 or folate deficiency and should be reviewed.
Signs of heavy bleeding
Heavy periods, black stools or visible bleeding may suggest blood loss and should be discussed promptly.
Unexplained weight loss
Unexplained weight loss is not a typical deficiency sign alone and may need broader medical investigation.
Yellow-toned skin
Some people with B12 or folate deficiency anaemia may develop pale or slightly yellow-toned skin changes.
All Symptoms
Anxiety
Feeling unusually anxious, unsettled or overwhelmed can sometimes appear alongside wider deficiency symptoms.
Balance problems
Unsteadiness, tripping or changes in walking may suggest nerve involvement and need medical review.
Brain fog
Brain fog may feel like slower thinking, poor focus or difficulty keeping track of tasks.
Brittle nails
Brittle, weak or spoon-shaped nails may sometimes be seen with iron deficiency or anaemia.
Digestive symptoms
Gut symptoms may matter because some digestive conditions can affect absorption of B12, iron or folate.
Disturbed vision
Visual changes can occur with B12 deficiency, but new or worrying changes need prompt assessment.
Dizziness
Dizziness or light-headedness can occur with anaemia, iron deficiency or several other medical conditions.
Extreme tiredness
You may feel unusually exhausted, drained or unable to recover your normal energy despite rest.
Feeling faint
Feeling close to fainting may be linked to anaemia or other causes and should not be ignored.
Feeling unusually cold
Feeling colder than usual may occur with anaemia, iron deficiency or thyroid-related problems.
Hair shedding
Increased hair shedding can have many causes, including low iron stores and thyroid problems.
Headaches
Headaches can have many causes, but may appear alongside tiredness, dizziness or deficiency symptoms.
Irritability
Irritability or feeling emotionally sensitive may occur with tiredness, low mood or physical symptoms.
Low energy
Daily tasks may feel harder than usual, even when your routine has not changed significantly.
Low mood
Low mood can have many causes, but may occur alongside symptoms of vitamin B12 deficiency.
Memory difficulties
Short-term memory problems, forgetfulness or word-finding difficulty can be distressing and worth discussing.
Mouth ulcers
Recurring mouth ulcers may appear with B12 or folate deficiency, although other causes are common.
Muscle weakness
Muscle weakness can affect confidence, mobility and everyday function, particularly if it is worsening.
Numbness
Numbness or reduced feeling in the hands, feet or legs should be assessed carefully.
Palpitations
Palpitations can feel like racing, fluttering or skipped heartbeats and should be assessed in context.
Pins and needles
Tingling, prickling or crawling sensations can occur when B12 deficiency affects the nervous system.
Poor concentration
You may struggle to focus, follow conversations or complete work that normally feels manageable.
Poor sleep
Poor sleep can worsen fatigue and brain fog, but may also be part of a wider symptom pattern.
Reduced stamina
You may notice exercise, stairs or walking longer distances feel harder than they used to.
Restless legs
Restless or uncomfortable legs may be linked with low iron stores in some patients.
Shortness of breath
Breathlessness can occur with anaemia or iron deficiency, especially during exertion or everyday activity.
Sore tongue
A sore, red or burning tongue can occur with B12 or folate deficiency symptoms.
Weakness
Weakness can feel like heavy limbs, reduced strength or difficulty managing normal physical activities.
Symptoms that may point more towards B12 deficiency
B12 deficiency can affect the nervous system, so symptoms involving sensation, balance, thinking or vision should be taken seriously. NICE notes that vitamin B12 deficiency can lead to neurological and mental health problems, including cognitive impairment.
Balance changes
Feeling unsteady, clumsy or less confident walking may need a focused neurological assessment.
Brain fog
Mental cloudiness, slower thinking or poor concentration may appear alongside physical or nerve symptoms.
Memory changes
New memory problems can feel worrying and should be considered alongside other B12-related symptoms.
Mouth ulcers
Mouth ulcers can occur with deficiency, but should be interpreted with the wider symptom picture.
Numbness
Reduced sensation or altered feeling can be important, especially if it is spreading or worsening.
Pins and needles
Tingling in the hands, feet or legs may suggest nerve involvement and should be reviewed.
Sore tongue
A sore, burning or red tongue can appear in B12 or folate deficiency.
Visual disturbance
New or unusual changes in vision should be assessed promptly, especially with neurological symptoms.
Symptoms that may point more towards iron deficiency or anaemia
Breathlessness
You may feel breathless on stairs, walking quickly or doing activities that were previously easy.
Dizziness
Light-headedness may appear when anaemia or iron deficiency affects energy and circulation.
Heavy periods
Heavy menstrual bleeding can contribute to iron deficiency and should be discussed during assessment.
Pale skin
Looking paler than usual can occur with anaemia, although it may be subtle.
Palpitations
A racing or pounding heartbeat can occur with anaemia and should be medically reviewed.
Poor stamina
Reduced stamina may make exercise, work or daily tasks feel unusually difficult.
Restless legs
Restless legs can sometimes be associated with low iron stores and may need ferritin testing.
Tiredness
Persistent tiredness is one of the most common reasons people seek help for iron deficiency.
When symptoms overlap it may not be one single deficiency
Many symptoms are shared across B12 deficiency, pernicious anaemia, iron deficiency and anaemia. They can also overlap with thyroid problems, inflammation, diabetes, stress, sleep problems, heart conditions, lung conditions and neurological issues.
For example:
- Tiredness may be linked to B12 deficiency, low iron, anaemia, thyroid disease or poor sleep
- Brain fog may be linked to B12 deficiency, stress, low mood or other medical conditions
- Breathlessness may be linked to anaemia, heart or lung conditions, anxiety or other causes
- Pins and needles may be linked to B12 deficiency, nerve compression, diabetes or other causes
This is why I do not recommend guessing based on symptoms alone. A careful history, examination where needed and targeted blood tests can help identify what is more likely.
B12 Metabolic Clinic is not an emergency service
Please seek urgent help through NHS 111, 999 or A&E if you have severe chest pain, sudden shortness of breath, fainting, weakness on one side of the body, new confusion, black stools, heavy bleeding, rapidly worsening symptoms or anything that feels severe, sudden or unsafe to wait.
If you have new or rapidly worsening neurological symptoms, severe weakness, problems walking or symptoms that feel unsafe to wait, please seek urgent medical advice.
Book a signs and symptoms review in Reading
If you recognise several symptoms on this page, or your blood results do not seem to explain how you feel, I can help you take a structured look at what may be going on.
I can review your symptoms, previous results, diet, medication, medical history and risk factors, then advise whether private blood tests, treatment or referral may be appropriate.