Distorted sense of smell can have various causes, ranging in severity from 'worrying' to 'serious'. Finding the true cause means ruling out or confirming each possibility – in other words, diagnosis.
Diagnosis is usually a complex process due to the sheer number of possible causes and related symptoms. In order to diagnose distorted sense of smell, we could:
Do you have sensations of unpleasant smells for no apparent reason?
Possible responses:→ No / don't know
→ Occasionally / moderate
→ Often / definite
Sensations of unpleasant smells are a symptom of zinc deficiency.