We’ve known that parosmia is a feature sometimes of recovery from smell loss, long before the Covid pandemic. Such a large number of sufferers appearing at once has meant that doctors and researchers are prioritising this difficult condition, so let me share with you some important tips if this affects you.
What is it?
Parosmia is the distortion of a smell that is present and that other people can smell too. The smell might be something close to you, like a cup of coffee, or something in the atmosphere, like the smell of burning leaves. For others, the smell is as it should be, but to you the smell could be foul or even make you feel nauseous. Note this is different from phantosmia, which is smelling something that isn’t present in the atmosphere. These smells are phantoms. This article deals with parosmia only.
How did it happen? and other important things to know
Our sense of smell is not a simple mechanism. There are many steps in the process, and once the smell message (the part where airborne molecules enter the nose and alight on the receptors) has passed through the olfactory nerves into the brain, a complex firing of the brain in many regions happens. For this reason, there is not yet 100% certainty where this happens, but let me outline what we do know.
- It seems that certain foods and healthcare products are the main culprits with parosmia. These include coffee, onions, garlic, fried foods, some meats, anything roasted including peanuts, some toothpastes and other personal care items. There is now scientific evidence for which odorant molecules cause this. Eliminating your trigger food items and switching to unscented body care is helpful.
- When the virus gets into the system, it can cause damage to the olfactory tissue in the nose, the place where the smelling happens.
- The olfactory system regenerates daily, throughout our lives, and this is why recovery is possible.
- Sometimes, though, recovery is incomplete or miswired. It is thought that this is what causes parosmia.
- There is also a theory, with Covid, that there is a problem higher up in the brain that is causing the distortion. One piece of research found that people who had post-Covid parosmia had changes to the part of the brain that signals disgust. However, it is not clear whether constant feelings of disgust made this part of the brain light up in scans, or whether parosmia in some way affected this part of the brain to influence a “disgust” response when smelling. No one knows for sure.
- Research has shown that people who have parosmia have a slightly higher recovery rate than people who never had it. Parosmia is seen as a sign of recovery.
- Young women seem to be particularly affected both in terms of numbers and how they respond.
You have parosmia. Now what?
- Know what triggers you, and avoid those foods
- Know what foods you can tolerate, and stick to those
- Sometimes foods can go from tolerable to disgusting overnight, so keep and open mind and keep trying new things if you can
- Spicy condiments might help
- Cinnamon chewing gum seems to be good for many, and can also distract from other smells in the environment
- Keep an eye on your nutrition. If you are reduced to eating only a few foods, make sure to supplement with vitamins and/or meal replacement shakes. Do avoid “protein shakes” such as you find in health food stores. Too much protein, without the other things you get from a normal diet, can put stress on your kidneys. If you are not sure, ask a pharmacist.
- Pair bland foods (plain pasta, rice, etc) with spicy or other trigeminal foods such as ginger, wasabi, soy sauce. Asian foods are great for this.
Smell training?
Smell training! A study that came out during the pandemic showed that people who have parosmia who smell train feel better. There is no way to accurately measure how bad parosmia is, we can only go by how people respond to questionnaires. However, when asked how they were doing after four months of smell training, people seem to feel better as well as more positive about their recovery. We know that smell training can hasten recovery. So it makes sense that it will also hasten recovery from parosmia.
If the smells in your smell training kit are distorted and make you feel sick, seek out things to train with that don’t. You could try vanilla from the kitchen cupboard, essential oils from your pharmacy, or even a shampoo brand that you can tolerate. The main thing is that the smell is strong when you go to smell it. Don’t suffer by training with something you think is revolting!
You can read the full article on smell training and parosmia here.
