Hyposmia is when a person loses part or all of their sense of smell. It can be disconcerting for an individual, but it can also have more serious implications.
Scientists say that the human olfactory system, which governs the sense of smell, can detect between 10,000 and 100 billion different odors.
The sense of smell can help create and recall memories, and it can add to the pleasure of many everyday experiences, improving a person’s quality of life.
Olfactory information also plays a crucial role in keeping a person physically safe. A loss of sense of smell can increase the risk of not noticing warning signs, such as the smell of gas, fire, or spoiled food. It can also indicate a more serious condition that needs medical attention.
According to the National Institutes of Health, 12% of adults in the United States have some loss of their sense of smell. This issue becomes more common with age.
Possible causes of hyposmia
- allergies
- a head injury
- infections, such as the flu
- small growths called polyps in the nose or sinuses
- a deviated nasal septum
- chronic sinus problems
- smoking
- a hormonal imbalance
- dental problems
Some
These include:
- several antibiotics, including ampicillin and tetracycline
- some antidepressants, such as amitriptyline
- certain antihistamines, such as loratadine
Other factors that could contribute to a loss of the sense of smell include:
- long-term exposure to certain chemicals
- tobacco smoking
- the use of recreational drugs, such as cocaine
- radiation treatment for cancers of the head and neck
Hyposmia can also be a sign of other health issues, including the following neurological conditions:
The findings of a 2013 study of 50 people suggested that 40% of those with MS may have at least a partial loss of their sense of smell.
A reduced sense of smell does not necessarily mean that a person will develop one of these conditions, but some experts have suggested that a smell screening test could aid early diagnosis.
Other conditions that can affect the sense of smell include:
Researchers have also found that people with type 1 diabetes can have trouble detecting and distinguishing scents.
A study showed that the more discomfort these individuals experienced as a result of diabetic nerve damage, called diabetic neuropathy, the more problems they had with their sense of smell.
Hyposmia is the partial loss of the sense of smell, but some people may experience
For example, anosmia is the complete loss of the sense of smell.
Some people have anosmia from birth, but it can sometimes result from a head injury, a problem with the nasal passages, such as chronic inflammatory nasal or sinus disease, or a severe viral infection of the upper respiratory tract.
Other types of smell dysfunction are:
- Parosmia, which is when the perception of smells becomes distorted, so smells that used to be pleasing start to seem unpleasant, or an odor appears to change in intensity.
- Phantosmia, which is when a person believes that they can smell something, but it is not actually there.
Hyposmia that is due to a seasonal allergy or a cold usually improves without treatment, but some medications and types of therapy to retrain the sense of smell may help.
If a person loses their sense of smell after a head injury or a significant inflammatory injury to the olfactory system, a complete recovery may not be possible.
According to the Anosmia Foundation, up to 22% of cases have no clear cause.
Many people start to lose their sense of smell as they become older. This loss can increase the risk of eating spoiled food and not noticing the signs of danger, such as a fire. It can also indicate a health problem that may need attention.
People who start to lose their sense of smell should seek treatment to ensure that these changes do not cause additional health and safety problems and to get treatment for any underlying conditions.
Installing and maintaining carbon monoxide and smoke alarms in the home can help protect people who have started to lose their sense of smell.
People should also use caution when working with potentially toxic household chemicals and check any food expiration dates.