A CKOS community member recently described losing their sense of smell months after nasal surgery to correct a deviated septum. They wondered whether the operation or a later illness was responsible.
Chrissi from CKOS explains that both factors can play a part in surgery and smell loss.
A septoplasty aims to straighten the nasal septum and improve breathing. Sometimes it also improves smell by allowing better airflow. In other cases, it may reduce airflow if the internal shape of the nose changes.
Every surgeon uses slightly different techniques. Those who focus on functional surgery try to preserve or improve smell, while cosmetic procedures that shorten or narrow the nose can unintentionally reduce airflow to the olfactory area.
Research supports this mixed picture. A review of fourteen studies involving almost one thousand people found that septoplasty can either improve or reduce smell depending on surgical technique and the changes made to airflow (Rhinology, 2020).
When a virus is the real cause
Even after successful surgery, smell loss can appear later if a virus damages the olfactory system. Many viruses, not only Covid, can cause this.
If you experienced a lingering or unpleasant odour at the same time, that is often a clue.
Phantosmia means sensing a smell that is not present, such as a constant sweet or smoky scent.
Parosmia means real smells are distorted or unpleasant.
These sensations often signal that nerves are healing, even if it does not feel like progress.
Taste vs smell: what is really happening
People often say their taste is fine when they really mean flavour. True taste detects only five sensations: sweet, salty, sour, bitter and umami. Flavour comes from smell.
If you can taste salt or sugar but food still seems flat, your taste buds are fine. It is your sense of smell that is affected.
As you chew and swallow, air carrying odour molecules travels from your mouth to your nose, a process called retronasal olfaction. When that airflow is blocked or the olfactory neurons are damaged, flavour fades even though true taste remains.
What scans can and cannot show
Smell loss rarely appears on routine scans. The olfactory nerves are thinner than a hair, and standard imaging cannot pick them up. Only specialist MRI equipment can sometimes show the olfactory bulbs, so many people are told their scans are normal even when their smell loss is genuine.
Smell training and recovery
For most people with post-viral or surgery-related smell loss, the best-evidenced approach is smell training. Research shows that steady practice helps the brain rebuild lost connections.
Try to:
- Practise twice daily, every day, for at least four months
- Use familiar, distinct scents such as rose, lemon, clove and eucalyptus
- Keep notes on small changes in perception
Even a faint flicker of smell is a sign that the nerves are still alive. Like learning a musical instrument, progress comes from repetition and patience.
Smell training can sometimes get unfair criticism online. It is common to see frustration or disbelief when results are slow, but research consistently shows that most people benefit from it. It is not a quick fix, yet it gives the brain the best chance to recover.
You can read more about the science behind it in our article Smell training: why it’s the number one tool for recovery.
Mindset matters
Smell loss affects both body and mind. It can feel like a constant emotional challenge, and progress is rarely linear. Keeping up your routine, noticing small improvements and connecting with others who understand can make a real difference.
Recovery takes determination, but the habits you build through smell training can help you regain confidence as well as function.
Key Takeaway
Surgery and smell loss are sometimes linked, but viruses are a more common cause. Recovery is often slow, yet daily smell training gives the brain its best chance to re-learn smells and rebuild confidence.
