8 amazing things that dogs smell and humans can’t

Unlike humans that interpret much of the world through their eyes, dogs use their instinctive sense of smell to know a lot of things going on around them.

Humans are known to have between 5-6 million olfactory receptors, but studies show that a dog’s nose has between 125-300 million receptors. This makes our furry friends smell 40-50 times stronger than humans.

Little wonder, we rely on canine’s superpowers to sniff out missing persons, diseases, and drugs. Their nose is built to interpret odors, and it takes just one sniff to get detailed information about a particular person or analyze a situation.

Don’t be surprised, a dog can tell if you’re a female or male, what you’re feeling if you’ve been around other animals, and even areas you visited lately.


All these are possible because the nasal cavity of dogs has an intricate olfactory system that carries unique nerve cells that connects to the brain directly. These nerve cells help dogs detect all kinds of odor and information, including those unknown to humans.

Another thing again is that dogs have a fold of tissue inside their nose that separates breathing and smelling. This makes them smell better than humans that smell and breath through the same air passage.

A dog’s nose extends to the back of their throat, and this allows them to sniff things intensely.

However, note that not all breeds of dogs are created equal on the sniff scale. Dogs with longer snouts, like the bloodhound, have more space for the nerve cells that detects smell than dogs like pugs with shorter noses.

Notwithstanding, all dogs are incredible sniffing machines, no matter the breed.

Below are some amazing things that dogs smell and humans can’t:

Missing persons

Some dogs called “Search and Rescue (SAR) dogs” are trained to locate missing people by following specific scents. They can trace hikers lost in the woods, elderly people who wandered off and lost children.

Cadaver dogs, for example, are used to find victims of accidents, homicide, or natural disasters.

These canines tend to follow airborne microscopic particle scents emitted from humans. They are capable of tracing the scent of a particular human, whether that person is out in the woods, in a crowded area, or under piles of debris. They even detect corpses underwater.

The amazing abilities of a SAR’s dog’s nose have saved many lives today.

Explosives and illegal drugs

Detection dogs are capable of sniffing out illegal drugs using their superior sense of smell. They can detect explosives and all kinds of contrabands.

Some dogs, called the “Narcotic Detection Dogs” are very sensitive to the scent of drugs and can pick up even the slightest residue of the drug.

Another class, called the “Explosive Detection Canines” is trained to detect specific chemical vapors produced from explosives.

Most times, a Pavlov style of repetition and reward is utilized to trace the target scent.

When the drug-sniffing dog senses the presence of contraband in a particular spot, they tend to paw and dig at the spot.

In the case of the Narcotic Detection Dogs, they utilize a more passive approach by sitting in front of the area with traces of explosives.

Sniffer dogs help to ensure safety at hospitals, airports, businesses, schools, vehicles, boats, and homes.


Dogs are now an important tool used to know people who are COVID-19 positive, and the interesting part is that they also detect asymptomatic people.

A dog’s keen sense of smell is now employed at the airport to screen people before they get on an airplane or attend events such as sports or concerts in large arenas.

Scientists have studied that humans give off volatile organic compounds (VOCs) when sick, and these molecules leave an odor on the body when they evaporate.

One popular use of a dog to screen people for COVID is seen in the Miami Heat basketball team. They screen fans before games begin and so far the results have been accurate.

Overall, there is a future for canines as a major player in stopping the spread of coronavirus.


Some dogs are trained to recognize seizures 12-15 minutes before the episode occurs. These dogs are called “Seizure Alert dogs.”

Scientists believe that humans produce a unique scent before a seizure and dogs can smell it.

Most times, Click and treat training methods are employed to teach dogs how to alert its partner to prepare for seizures. These dogs are also trained to fetch medications, alert caretakers, get cellphones and even open the door for medical personnel.

Service dogs provide lots of help to people with disabilities, from more independence to peace of mind and confidence.

Pregnancy and ovulation

A dog can detect pregnancy in its early stage, even before a woman sees a need to take a pregnancy test. Canines are very sensitive to the smell of urine of both humans and animals.

The hormonal changes during ovulation and pregnancy affect the scent of urine, and a dog’s nose is able to trace this smell.

Usually, dogs are attracted to the scent produced by females when their hormonal levels change. That’s why they tend to sniff the crotch area more often.

Farmers have also maximized dogs’ sense of smell to sniff cow urine to know if the animal is in heat.

Another important advantage of dogs sniffing urine is their ability to detect ovarian cancer, which could help save a patient in the early stage of the condition.


The Diabetes Assistance (DA) dogs can detect changes in blood sugar levels with one sniff of a human’s breath.

When your glucose level drops, there is always a change in the way your breath smells, and the DA dogs are excellent in picking up the scent.

When these dogs detect this scent, they often alert their owner or the person involved by pawing or nudging them with their nose. This way, the owners can take immediate action to prevent dangerous diabetic episodes.

Natural Disasters

The sensory cells at the end of dogs’ noses allow them to detect changes in the atmosphere. This makes it possible for dogs to predict natural disasters that are about to occur, including a snowstorm, heatwave, earthquake, tornado, flooding, or hurricane.

Dogs can sense impending doom long before humans start to have a clue. Many dogs have heard well-deserved heroic legacy due to their impact in saving people from natural disasters.

Their owners

Even when you blindfold a dog and allow them into a room full of people, without any sound, the dog will still move to meet their owner with a brief sniff.

Dogs often recognize their owners’ distinct scent that is linked to positive memories, such as affection, playing, praise, food, and security.

These activities or actions create a strong bond between dogs and their owners.

Most times, dogs show love for their family by head tilting, tail wagging, nuzzling, alertness, happy barks, and staring. Little wonder these fantastic furry friends are man’s best friends.


Dogs have a well-developed sense of smell that is 1,000 to 10,000 times more powerful than that of humans. This makes it possible for them to discover what humans can’t know naturally.

Dogs can detect their owners, missing persons, explosives or drugs, cancer, diabetes, epilepsy, pregnancy or ovulation, natural disasters, and even COVID. Isn’t these creatures amazing?

You can get yourself a dog today and let them help you discover some amazing things you wouldn’t know ordinarily.



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