The Science Behind Scent: Why Your Nose Adapts To Cologne

Have you ever wondered why you can't smell your own cologne? This phenomenon is called olfactory adaptation or 'nose fatigue'. It occurs when your brain gets used to a particular smell and stops noticing it. This is a natural evolutionary response that helped humans identify and avoid danger. While it may be frustrating to not be able to smell your cologne, there are ways to remedy this, such as taking a break from the fragrance and switching to a different scent.

'Nose Blindness' or olfactory adaptation means your nose gets used to the scent

Nose Blindness or olfactory adaptation means your nose gets used to the scent

It is frustrating when you can no longer smell your cologne. However, this is a natural evolutionary response called olfactory adaptation or 'nose blindness'. Our sense of smell is designed to help us identify new odours that might signal danger or food. Once our brain categorises a scent as harmless, it is pushed to the background so that our nose is free to detect new smells. This process is vital, allowing our olfactory sensors to quickly identify any slight changes in our surroundings, especially scents that could be dangerous.

When you first apply cologne in the morning, you can smell it. However, as the day goes on, your nose gets accustomed to the scent. This is why you might think you haven't applied any cologne at all. Your brain has decided the scent is not a threat and has blocked it, making your nose available to detect new scents.

This phenomenon is not unique to humans. Scientists have observed olfactory adaptation in animals, from 1mm worms to flies and rats. If these animals are exposed to a smell from a young age or repeatedly, they will eventually stop noticing it.

There are ways to combat nose blindness. One way is to build a 'fragrance wardrobe', where you have an array of different colognes for different moods and occasions. That way, your nose doesn't get used to the same scent, and you can continue to smell it throughout the day. You can also experiment with different perfuming techniques, such as spraying above you in a cloud or spraying behind your ear, to stimulate your nose and play with olfactory perceptions.

Your brain categorises the odour, making it less discernable

The human olfactory system is a fascinating and complex mechanism that often plays tricks on us. One such trick is olfactory adaptation, or 'nose fatigue', which is what happens when you can no longer smell your cologne.

When you first apply cologne in the morning, you can smell it. However, as the day goes on, your brain becomes accustomed to the scent, and you gradually stop noticing it. This is because your brain has categorised the odour as harmless, and therefore stops it from reaching your conscious awareness. This is an evolutionary mechanism that allows your brain to focus on new and potentially dangerous smells.

This process happens very quickly, and it occurs in animals as well as humans. Scientists are not sure why our brains become accustomed to a particular smell so quickly, but they do know that it happens to everyone.

So, if you can no longer smell your cologne, don't worry—it doesn't mean that the scent has disappeared. Your brain has simply categorised the odour, making it less discernable.

Your perfume may be evaporating too quickly

If you find that you can't smell your perfume anymore, it may be evaporating too quickly. There are several ways to combat this. Firstly, try moisturising before applying your perfume. This provides a "cushiony, nourished canvas" for your fragrance to settle onto, helping it to dry down more effectively and last longer.

Secondly, avoid rubbing your wrists together after applying perfume. This can crush the delicate scent molecules, altering the scent and causing it to fade faster. Instead, apply your perfume and let it sit and set into the skin.

Thirdly, consider the type of perfume you are using. Light fragrances composed of volatile notes, such as citrus, tend to "blast off from your skin" but then dissipate quickly. Opting for a perfume with deeper notes and a higher concentration, such as an eau de parfum, might help to make the scent last longer.

Finally, try spraying your perfume onto your clothes as well as your skin. Scent can often last longer on cloth, so this can be a good way to make your fragrance linger for longer. However, be sure to spot-test before spraying, as some perfumes can stain fabrics.

You may have olfactory disorders or less sensitive olfactory sensors

It is possible that you have an olfactory disorder or less sensitive olfactory sensors if you are unable to smell your cologne. Olfactory disorders can be caused by a variety of factors, including aging, viral infections, head trauma, and exposure to certain chemicals. These disorders can result in a reduced sense of smell or even a complete loss of smell.

Additionally, the sense of smell can decrease with age. This is because the olfactory sensors, or smell receptors, in the nose can become less sensitive over time. This is a normal part of aging and is not typically a cause for concern. However, it can affect your ability to smell your cologne or other scents in your environment.

If you are concerned about your sense of smell, there are some steps you can take to try and improve it. One method is to train your nose by exposing yourself to different scents and trying to identify them. This can help improve your olfactory sensors' sensitivity and ability to detect different odors. Another way to enhance your sense of smell is to stay hydrated, as dehydration can negatively impact the sense of smell. Drinking enough water can help keep your olfactory system functioning optimally.

In some cases, your inability to smell your cologne may be due to something called olfactory adaptation or "nose fatigue." This is when your brain becomes accustomed to a particular smell, causing you to stop noticing it. Our brains are wired to focus on new or unusual smells, particularly those that may signal danger or the presence of food. As a result, once a scent is categorized as harmless, our brains may block it to make room for new scents. This is why you may stop smelling your cologne after a few hours or a few months of wearing it consistently.

To remedy this, you can try taking a break from your cologne for a while and switching to a different fragrance. This will stimulate your nose again and help your sensors become more reactive. Additionally, you can experiment with different perfuming techniques, such as spraying above you or on your clothes, as these can affect how you perceive the scent.

You can train your nose to be more reactive

It is perfectly normal to stop smelling your cologne after a while. This is called olfactory adaptation or "nose fatigue". It happens because our sense of smell evolved to help us identify odours that might signal something important, like danger or food. Once our brain categorises a scent as non-threatening, it blocks it to make our nose available to new scents.

However, if you want to be able to smell your cologne for longer, you can train your nose to be more reactive. There are different stages in nose training, and you can move from one stage to the next as you master the art of the stage you're on.

Beginner stage

Start by consciously attempting to smell scents and aromas around you. Examples include coffee, fruit, chocolate, herbs, tea, and olive oil. Don't be discouraged if you can't remember a scent or confuse different smells. At this stage, you're just choosing to smell. Once you're taking deep breaths of smells and aromas without having to remind yourself, you're ready to move on to the next stage.

Intermediate stage

The intermediate stage is based on differentiating scents. Choose three different types of smells, such as wood, floral, and fruity. Examples include coffee beans, rose petals, and orange peel. Crush the coffee beans and grate the orange peel to release more of their scent. This stage will sharpen your sense of smell, and the results will be obvious after a few weeks of exercise.

Advanced stage

The early hours of the morning are the time when our sense of smell is sharpest. Smell 3 to 5 different aromatics first thing in the morning. You can use spices such as cinnamon and vanilla. Crush the spices slightly and keep them in a sealed container. Inhale a deep breath and take time to think about what you're smelling. Don't rush this stage and give each aroma time to register in your brain. Smell these 3 to 5 aromas every day for at least a few consecutive days.

Other tips

• Smell everything and anything: spices, leaves, food, grass, flowers, etc.
• Try to make mental notes of how things smell and see if you can recognise the scent in other things.
• Try to pick out individual spices from a spicy dish.
• "Sweet" isn't actually a smell, but rather things we associate with smelling sweet, like caramel or vanilla.
• Make small habits throughout your day, like deconstructing the notes in your coffee or taking a brief moment to smell your meals.
• Drinks are a great source of scent, whether alcoholic or not.
• Practice smelling individual scents before moving on to perfumes.
• If you have a body lotion with orange notes, for example, start by smelling an orange for a few days, then try smelling your lotion and see if you can pick up the orange notes more clearly.

Frequently asked questions