Snug Vest

Autistic Child with Olfactory Dysfunction Smelling a Daisy Flower

Sensory overload is something that we all experience to a degree, but those with Autism Spectrum Disorder often also have a Sensory Processing Disorder or have sensory integration difficulties. This means autistic individuals tend to be more easily and more heavily impacted by their sensory surroundings. This is a seven part series in which I will address the different types of sensory disorders, help you identify them, and find some solutions. This fourth blog post addresses Olfactory Dysfunction

Our sense of smell is responsible for some of our most instinctual reactions.  It can grab our attention instantly.  Imagine the first whiff of a smoky barbeque out in your backyard, even just describing it can bring back a strong memory of that smell.  On the contrary, try to remember rolling down your car window while driving through farmlands filled with manure.  Pungent, isn’t it? Anything relating to smell, also known as olfactory, can inform us of our surroundings and trigger our muscle memory in milliseconds.  Olfactory Dysfunction is considered a Sensory Processing Disorder involving an altered sensitivity to smells and can result from a variety of factors such as age, viral infections, exposure to toxic chemicals, or neurodevelopmental disorders such as Autism Spectrum Disorder (ASD).   This can raise a variety of sensory issues that affect people on a daily basis, depending on whether the individual is hypersensitive or hyposensitive.


Autistic Child with Olfactory Dysfunction who is hypersensitive to food

Being hypersensitive to smell comes with a range of problems that most people may never even be aware of.  For example, you might know someone who is a picky eater, but the cause could be that they are overwhelmed by the smell of say, fried eggs.  Or, a person may dislike a room because of it's smells and that will be enough for them to avoid that room altogether.  A faint smell to the average nose is amplified to someone who is hypersensitive to smell, and rarely in a positive way.  This can affect their relationships and their ability to meet new people.  A stranger’s distinct smell, whether it is their breath or perfume, can affect an olfactory hypersensitive person’s first impression significantly, so much that it can override all other characteristics.

How do I identify hypersensitivity to smell?

Like other Sensory Processing Disorders, the reactions to adverse stimuli are often knee-jerk, fight or flight responses.  As a child, these can come in the form of tantrums and meltdowns.  Hypersensitivity to smell may be a contributor to such behavior.  One sign may include vehemently avoiding certain foods because of their smell. For example, just being in a kitchen, let alone eating an aromatic meal, can be more than enough to dissuade a hypersensitive person!  They may notice bodily odours more easily and refuse to interact with whomever that smell is associated with.  Strong scents such as perfumes and soaps can also be extremely irritating and even nauseous to the person who is hypersensitive to smell.

A key part of identifying olfactory dysfunction is to notice that their experience with smell may be totally different from yours.  For hypersensitivity, it is to a point where a certain aroma instigates such a negative response, that they avoid all behaviours involving it.  It doesn’t matter what activity or person, a pungent smell can override the whole experience.

What techniques can I use to help someone who is hypersensitive to smell?

  • Verbally communicate any smells they may encounter beforehand so they can mentally prepare
  • Avoid using products with strong odours whenever possible
  • Use non-scented cleaning products
  • Avoid spicy and aromatic foods
  • Try nasal filters or Saline nasal spray
  • Find a friendly aroma and keep that close to fend off strong fragrances


On the other side of the spectrum, olfactory hyposensitive individuals have a much more difficult time sensing certain odours.  Unfortunately, this can result in smells such as noxious chemicals, smoke fumes and rotten food going totally unnoticed.  For most, the sense of smell is an important warning alarm but for hyposensitive people this is not the case.  Hyposensitivity can affect many aspects of their lives, for instance, interactions with people and objects are less distinguishable because they don't recognize specific smells they would otherwise be used to draw on past experiences.  Smell has an uncanny ability to evoke feelings and memories associated with that scent, which affects a hyposensitive individual’s ability to identify and categorize certain experiences right away.

How do I identify hyposensitivity to smell?

Olfactory hyposensitive people have a lack of sensitivity to smell and thus find it difficult to detect certain odours, even the most pungent ones that signal danger.  They may get sick noticeably more often from eating bad foods or find themselves in situations totally unaware of a smell that other people are complaining about.  Hyposensitive people may also seem curious and make more of an effort to identify objects and people by their smell, as their lack of olfactory sensitivity makes it more difficult to figure things out initially.  As children, a specific example may be with Scratch n Sniff stickers and having troubles identifying the smells associated with each.

Scratch and Sniff Stickers for Children with Olfactory Dysfunction and Autism

What techniques can I use to help someone who is hyposensitive to smell?

  • Verbally communicate the smells that exist around them i.e. when outdoors or in a kitchen cooking with different spices
  • Explain that they have to be more careful with the food or drink they consume because of their lack of smell
  • Try to have strong scented candles, air fresheners, soap and spicy foods around so they have opportunities to experience their sense of smell
  • Play smelling games i.e. blindfolding and then place a familiar item under their nose to have them guess what it is

If you liked this article, check out these:

             Goofy falling from Proprioceptive Dysfunction                                           Boy who is sensitive from Visual Sensory Processing Disorder

What is Proprioceptive Dysfunction?                     What is Visual Sensory Processing Disorder?



Person sensitive from Auditory Sensory Overload                                         Baby with tactile dysfunction

What is Auditory Sensory Overload?                              What is Tactile Dysfunction?

Written by Ryan Leung — October 23, 2015

Leave a comment

Wearable pressure vest to manage stress, ease anxiety, and help increase focus Click here to learn more
Looks like you're in the . Go to ? Yes please or No thanks.