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8. A Smooth, Sore, or Red Tongue
Some individuals with vitamin B12 deficiency develop glossitis, an inflammation of the tongue.
Symptoms include:
A swollen or smooth tongue
Redness
Burning sensation
Pain while eating or speaking
Mouth ulcers may also occur.
9. Vision Changes
Although less common, untreated vitamin B12 deficiency can affect the optic nerve.
Possible symptoms include:
Blurred vision
Double vision
Reduced visual clarity
Prompt treatment may help prevent permanent damage.
10. Frequent Dizziness
People with vitamin B12 deficiency-related anemia may experience:
Lightheadedness
Dizziness when standing
Feeling faint
These symptoms occur because the brain may receive less oxygen than it needs.
Who Is at Risk of Vitamin B12 Deficiency?
Certain groups are more likely to develop a deficiency, including:
Older adults
Vegans and strict vegetarians
People with pernicious anemia
Individuals with digestive disorders such as Crohn’s disease or celiac disease
People who have had stomach or intestinal surgery
Those taking certain medications, including long-term use of metformin or acid-reducing medications
Individuals with chronic alcohol misuse
Being in a higher-risk group doesn’t mean you will develop a deficiency, but regular monitoring may be appropriate.
Common Causes of Vitamin B12 Deficiency
Vitamin B12 deficiency can result from several factors:
Inadequate Dietary Intake
Because vitamin B12 is found mainly in animal-derived foods, people following vegan diets without fortified foods or supplements may not get enough.
Poor Absorption
Some people consume enough vitamin B12 but cannot absorb it effectively due to:
Pernicious anemia
Reduced stomach acid
Digestive disorders
Gastrointestinal surgery
Certain Medications
Long-term use of medications such as proton pump inhibitors (PPIs), H2 blockers, and metformin may reduce vitamin B12 absorption in some individuals.
How Is Vitamin B12 Deficiency Diagnosed?
A healthcare professional may recommend:
Blood tests to measure vitamin B12 levels
Complete blood count (CBC)
Methylmalonic acid (MMA) test
Homocysteine test
Additional tests to identify underlying causes if needed
Diagnosis should be based on symptoms, medical history, and laboratory findings.
Treatment Options
Treatment depends on the severity and cause of the deficiency.
Common approaches include:
Vitamin B12 Supplements
Mild deficiencies may be treated with oral vitamin B12 supplements.
Vitamin B12 Injections
People with severe deficiency or poor absorption may require injections prescribed by a healthcare professional.
Dietary Changes
Increase intake of vitamin B12-rich foods such as:
Fish
Meat
Poultry
Eggs
Milk
Yogurt
Cheese
Fortified breakfast cereals
Fortified plant-based milks
Can Vitamin B12 Deficiency Be Prevented?
In many cases, yes.