Zinc and anosmia: safe, practical guidance

Taking extra zinc without knowing the cause of smell loss may not help and can cause unwanted effects or interact with medicines. Products containing zinc should not be placed inside the nose because intranasal zinc has been linked to damage to the sense of smell.

Zinc supports normal body functions, and deficiency can affect taste or smell. Deficiency is only one possible explanation, however. Nasal inflammation from allergic rhinitis or chronic sinusitis can restrict airflow, while a common cold, COVID-19, or Long COVID may be associated with smell loss through a different pathway.

A clinician considers diet, digestive problems, medicines, nasal symptoms, recent infection, and examination findings before deciding whether testing or supplementation makes sense. This avoids treating the nutrient level while overlooking another cause.

Tell your clinician or pharmacist about every supplement and medicine you take, including the product strength and form. Do not exceed the label or combine several zinc products. Food sources can be discussed as part of a balanced diet, but dietary changes should account for allergies and other health needs.

Record when smell loss started, whether the nose is blocked, and whether it followed an infection or head injury. Keep smoke and gas alarms working and use storage instructions and expiry dates to judge food safety rather than smell alone.

Seek clinical advice if smell loss persists after congestion has cleared, has no apparent cause, or affects appetite and daily safety. Urgent assessment is needed when it follows a significant head injury or appears with facial weakness, speech difficulty, confusion, severe headache, new vision trouble, or limb weakness.

If a supplement causes repeated vomiting, severe abdominal pain, faintness, breathing difficulty, or swelling of the lips or tongue, stop taking it and obtain urgent medical help.

Ask whether your history suggests deficiency, whether testing would change care, which oral form is appropriate if treatment is advised, and whether zinc could interfere with any antibiotic or other medicine you use.