University of Reading study unlocks the parosmia puzzle

We’ve followed the progress of Dr Jane Parker’s work at The Flavour Centre, University of Reading for some time. Now we’re delighted to announce the results are in – and for the first time, scientists can pinpoint the molecules that trigger parosmia.

What is parosmia?

If you experience parosmia, you’ll be very familiar with what it is and the effect that it has on you. But it can be harder to explain to others who haven’t experienced it, and the lines between parosmia, phantosmia, or other smell disorders may be less clear.

ENT Consultant Mr Simon Gane was also involved with this study. As an experienced clinician working with patients with smell disorders, he suggests the characteristics of parosmia are:

• Something that is triggered – the odour of food, drink or other objects that set of a parosmic response needs to be present. 
• Parosmic experiences are relatively short-lived – the sensation doesn’t linger when the odour source has gone.
• The smell you’re experiencing is an altered version of what you’re actually smelling. For example, if coffee is the trigger, what you actually smell isn’t what you normally recognise as coffee.
• The smells experienced are disgusting or unpleasant.

The Parosmia Study 

Patients sharing their experience of parosmia point to some common triggers, especially coffee, onions and roasting meat. Starting with coffee, Dr Jane Parker created a study to try and identify specific odour molecules responsible for triggering that disgust response so familiar to people with parosmia.

Working with people experiencing parosmia plus a control group who had normal sense of smell, Jane broke the aroma of coffee down into all its different parts and ran each in turn by her volunteers.

Firstly, she was able to conclude that it didn’t matter how poor the sense of smell was, parosmia happened anyway. Parosmia is not linked to ability to smell.

Most excitingly, the results picked out two types of molecules, one containing sulfur and one containing nitrogen, as the triggers for parosmia. “These same molecules are found in lots of different foods,” Jane told the AbScent Presents webinar. “We now know there is a molecular basis for parosmia.”

It’s a great start, but it’s not a simple solution. Scientists still don’t really understand which odour receptors in the nose these molecules link to. As Jane says, “The more you look, the more difficult it gets – and the more interesting it gets”.

How will this help?

Understanding what is causing parosmia is the important first step in treating it. Simon Gane is very excited about the possibilities this research opens up. 

“This research is really powerful in helping patients right now. I can tell people what to expect, these are the kind of things that you might expect to be triggers, things to avoid” he says. Longer term, Simon is hopeful there could be medication that will offer some relief.

More information about olfactory sytstem

If you’d like to understand more about how smell works, you may be interested in these articles: https://abscent.org/insights-blog/blog/understanding-parosmia 

https://abscent.org/insights-blog/blog/coronavirus-affects-smell.

You can view all the webinars in full at YouTube/AbScent Anosmia Support

February 22, 2021