Ask the allergist is a regular feature in our newsletters where Dr. Julia Upton answers your questions!
Dr. Julia Upton is a Canadian allergist who is on staff at Toronto’s SickKids Hospital in the Immunology and Allergy Department. She is an Assistant Professor in the Department of Paediatrics at the University of Toronto and is the Section Chair of Food Allergy and Anaphylaxis with the CSACI. Dr. Upton is also a member of our Healthcare Advisory Board.
Please note: Dr. Upton is answering as an individual allergist and her answers do not constitute an official position of her affiliated organizations. Her responses are for informational purposes only and do not constitute specific medical advice, recommendations, diagnosis, or treatment. Please talk to your doctor about any concerns or questions you may have regarding your own health or the health of your child.
This month she answers your questions about the smell of a food and inhalation of airborne proteins.
Can I be allergic to the smell of an allergen? Can I have an allergic reaction by smelling food?
The smell/odour of food does not contain protein, which is what causes an allergic reaction. Someone who is allergic to a particular food may feel anxious or uncomfortable if they smell it. However, smelling a food is different from inhaling airborne proteins. Examples include proteins sent into the air by cooking, the powder of food being blown into the air, or the food entering the air from crushing/grinding.
What is the difference between smell and inhalation?
The smell of food does not involve food protein whereas the inhalation of the food means the food particle/protein is inhaled. For example, the smell of peanut butter does not cause an allergic reaction but crushing peanuts and inhaling peanut powder could cause an allergic reaction.
In another example, the smell of fish does not have protein, however cooking fish (sizzling on a frying pan or boiling it) can put the protein in the air and lead to inhalation by someone allergic to fish.
How can allergic reactions through inhalation occur?
During inhalation, the food protein gets into the body through the nose and lungs. This inhalation can cause a mild reaction or asthma-like symptoms. Reactions can be severe, but this is rare.
Thank you, Dr. Upton, for your insightful and helpful answers!
Learn more about smell vs. inhalation here. Direct ingestion of an allergy-causing food poses the greatest risk for most people with food allergy. Understanding how to avoid contact with a food allergen will help prevent allergic reactions.
Do you have a question you’d like to ask Dr. Upton in the months to come? If so, please send it along to us at firstname.lastname@example.org.Tags: ask the allergist, dr upton