How do eucalyptus/mint scents clear up a stuffy nose?



How do eucalyptus/mint scents clear up a stuffy nose?

In: Biology

They don’t.

We have different types of receptors in our noses, including receptors that are activated by cooling. I believe these receptors are used by the body to sense airflow within our noses. Mint contains menthol which stimulates those receptors in particular, giving us the sensation of airflow.

TL;DR mint stimulates receptors in our noses to give us the sensation of airflow, but it’s just a sensation and doesn’t actually clear anything up.

Mint and eucalyptus activate the temperature receptors in your nose (or wherever you ingest it), particularly those dealing with low temperatures. This activation is the same effect that happens when you eat a hot pepper, only the capsaicin in the peppers activate a different receptor (ones that respond to hotter temperatures).

Since the receptors that are activated are telling your brain “Hey I’m really cold”, the brain signals the blood vessels in that area to contract to prevent body heat loss. As the vessels contract, the nasal passages open up allowing you to breath easier.

*Edit: there, I’ve corrected the “contact”:”contract” problem lol.

The most popular response is wrong I think. Mint/Menthol/Eucalyptus do not actually reduce or clear nasal congeston they simply trick your brain into thinking you are breathing clearly through your nose.

I am a Pharmacist and my University Professor taught that menthol and eucalyptus activate cold (thermo) receptors when you inhale them into your nasal passage. These are the same cold receptors that are activated when you are inhaling normally via your nasal passages (focus on it now and feel the sensation of cool air in your nasal passage).
The activation of the receptors when your nose is blocked gives you the sensation of achieving adequate imhalation of air through your nose HOWEVER you will also be breathing in through your mouth aswell to compensate for the reduced intake of air through your nose.
Doing steam inhalations with or without menthol/eucalyptus can help to clear your congestion as the steam will help to dissolve the mucus blocking the nasal cavity.
Psuedoephedrine helps to clear nasal congestion by constricting the blood vessels in the nasal passage and reduce mucus formation.
The nasal passagea do not really increaae or decreaae in size it is the amount of mucus up there that restricts airflow.

Aussie bush on the summer rain is my all time favourite smell as an Aussie. I love the smell after a sun shower that comes from the earth mixed with the big gums and iron barks. It’s amazing.

It is likely that eucalyptus/mint scents do not clear up a stuffy nose. An article []( named The effect of inhaled menthol on upper airway resistance in humans: A randomized controlled crossover study looked at the effect on menthol on nasal congestion. Albeit a small study, it showed no statistically different between placebo and menthol. I was unable to find any other study on the subject. The reason many people have responded that it increases vasodilation is because there are studies of topical menthol showing this effect. Although smell is small amounts of the substance reaching your nose, we cant jump to the conclusion that it is similar to topical application. The most likely reason people ‘feel’ less congested is because menthol (mint) and likely eucalyptus are counter irritants. By slightly irritating your nasal passage, it feels like more air is passing through but in reality you are only sensing the air more acutely. More studies would be required to say that mint clears up a stuffy nose.

A related question: if they actually do something, why are mint and eucalyptus listed as “inactive ingredients”?

A stuffy nose usually isn’t stuffy because it’s filled with mucus, but feels stiff because the veins and tissue expanded due to inflammation

I once had a really ditzy coworker directly apply peppermint essential oil to the area under her nose to clear up the stuffiness. She screamed. Her mucous membranes were on fire. Some people are just not cut out for the real world.

Fun fact, it doesn’t work if you don’t have the ability to smell. I tested this while sick with covid.