For centuries, cat owners have noticed that their feline companions seem to detect when they are feeling unwell or experiencing a health issue. Cats have a much stronger sense of smell than humans, and some research has indicated they may be able to detect subtle chemical changes in the human body that occur with certain illnesses. While the evidence is still limited, some studies suggest cats may be able to smell chemical or hormonal changes associated with diseases like cancer, seizures, and diabetes. Though the mechanisms are not fully understood, a cat’s sniffing, staring, or clingy behavior when their owner feels ill may be their attempt to alert them to an underlying health problem. This article explores what science has revealed so far about cats’ potential ability to detect human illnesses.
Cancer
Studies have shown some evidence that cats may be able to detect cancer in humans. One study published in 2015 found that cats spent more time around urine samples from people with lymphoma, breast, and lung cancer compared to healthy samples (source). The cats showed interest in the cancer samples by sniffing, pawing, and vocalizing more. This suggests cats may be able to detect biochemical changes in urine caused by cancer.
There are also many anecdotal reports of cats paying close attention to cancer sites on their owners, often before a formal diagnosis. According to this source, some examples include cats constantly sniffing at moles before they were identified as melanoma, fixing their gaze on their owner’s breast before a breast cancer diagnosis, and insistently sniffing at the owner’s mouth before oral cancer was found.
While the empirical evidence is limited, these accounts suggest cats may be able to detect subtle odor changes, behavioral cues, or appearances changes caused by cancer. More research is needed to understand how cats discern these signals and determine if they can reliably detect cancer.
Diabetes
There is some evidence that cats may be able to detect dangerously low blood sugar in diabetics. One study conducted by researchers at Queen’s University Belfast in 2015 found that cats reacted differently when their diabetic owners were experiencing hypoglycemia. The cats vocalized more, sat closer to their owners, and sometimes even attempted to wake them up during hypoglycemic episodes. This suggests the cats may have detected scent changes triggered by the low blood sugar.
Anecdotal reports from diabetic cat owners also indicate cats can sense blood sugar drops. Many describe their cats nudging, licking, or biting them when blood sugar gets too low. It’s theorized cats may detect isoprene, a common organic compound whose levels fluctuate with changes in blood sugar. More research is still needed to fully understand how cats might detect hypoglycemia.
Seizures
There are many anecdotal accounts of cats seeming to sense oncoming seizures and alert their owners before the seizures happen. While the evidence is largely anecdotal so far, some cat owners firmly believe their feline companions are able to detect subtle behavioral changes that precede seizures (https://www.hepper.com/can-cats-detect-seizures/).
One theory is that cats may be able to detect subtle changes in human behavior, scent or pheromones that signal an impending seizure. There are stories of cats becoming agitated and vocal, or pawing and licking their owner insistently just before a seizure occurs. Some believe the cats are trying to warn their owners of what’s about to happen.
While cats do not appear to be specifically trained as seizure alert animals as some dogs are, their apparent ability to sense oncoming medical events is intriguing. More research would be needed to determine if cats can reliably detect pre-seizure changes. But the many accounts of cat owners believing their felines alerted them to seizures suggest cats may have useful sensory abilities we do not yet fully understand (https://blog.catbandit.com/can-cats-detect-seizures-exploring-the-phenomenon/).
Pregnancy
There are many anecdotal accounts of cats seeming to detect when their owner is pregnant before the owner even knows. While the mechanisms behind this ability are not fully proven, there are some compelling theories. One is that cats may be able to detect subtle changes in a woman’s hormones very early on in pregnancy through their advanced sense of smell.
One study conducted in 2011 found that cats were able to distinguish between the odors of pregnant and non-pregnant women’s sweat samples. The cats spent more time around the odors of pregnant women compared to non-pregnant women (Source). This suggests cats can detect incredibly subtle hormonal changes associated with early pregnancy through their sensitive sniffers.
Additionally, some speculate that cats may be able to sense slight changes in a pregnant woman’s body temperature. A pregnant woman’s basal body temperature is slightly higher, and cats may be able to pick up on this warmth. Their tendencies to sit or sleep on a pregnant woman’s lap more often may be related to detecting this change.
While the exact mechanisms are still being researched, many cat owners swear their feline knew they were pregnant before they did. Cats’ advanced senses allow them to pick up on the smallest physiological changes. More research needs to be done, but cats seem to have an uncanny knack for pregnancy detection.
Low Blood Pressure
Cats may be able to detect low blood pressure in their owners through subtle physical cues. When someone has low blood pressure, also known as hypotension, their body struggles to get enough blood to vital organs. This can cause symptoms like dizziness, fainting, fatigue, nausea, cold and clammy skin, and blurred vision.
Cats are very observant creatures and seem to recognize when their owner is not feeling well. They may notice if their owner’s skin suddenly feels colder or clammier, which could be a sign of dropping blood pressure. Cats also pay close attention to human behavior and movement, so they may detect subtle changes like dizziness or fatigue that accompany low blood pressure.
Additionally, cats have a strong sense of smell and may be able to literally sniff out changes in body chemistry when blood pressure drops. Research suggests cats can detect significant changes in hormones, neurotransmitters, and other biological markers through scent alone.1 This ability to sense chemical signals could allow cats to know when their owner’s blood pressure takes a dip before obvious physical symptoms appear.
While the exact mechanism is still being studied, many cat owners report their feline companions alerting them or even waking them up during bouts of low blood pressure. Paying attention to a cat’s concern could provide life-saving warning to take preventative steps or get medical attention when dealing with chronically low blood pressure.
Infections
There is evidence that cats may be able to detect respiratory infections in humans through changes in scent. One study found that 7.7% of cats living with COVID-19 positive owners tested positive for SARS-CoV-2 viral RNA, suggesting they were infected through close contact. While the cats showed no symptoms, it’s possible they detected changes in their owners’ scents that signaled illness. Cats have a strong sense of smell and their olfactory center has nearly 200 million scent receptors, far more than humans. They may pick up on volatile organic compounds released in skin secretions and breath that are biomarkers for infection.
Ongoing Research
In recent years, there have been a number of studies exploring cats’ detection abilities, especially related to illnesses. Cats have demonstrated impressive capabilities in detecting cancer, seizures, infections and other medical conditions in humans.
One major area of research has focused on cancer detection. According to a 2020 study published in PLOS One, cats may be able to detect certain cancers by sniffing urine samples (https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0241322). The cats were able to accurately identify urine from patients with prostate cancer 71% of the time. Researchers believe cats may be responding to biomarkers or subtle scent changes caused by cancer.
Another illness cats may be able to detect is seizures or epileptic episodes. Some cats have been observed alerting owners up to an hour before the onset of a seizure. According to a 2019 paper, this ability could be due to cats’ sensitivity to subtle physiological changes or pheromone alterations that happen before or during a seizure event (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6464590/).
Researchers continue to explore cats’ capabilities in detecting various illnesses. Advancements in this area could lead to new diagnostic tests and medical alert systems that take advantage of cats’ superior sense of smell and intuition. More research is needed, but initial findings suggest cats may provide invaluable aid in medical care and health monitoring.
Theories on Detection
There are several theories as to how cats are able to detect illness and other health conditions in humans. Much of it comes down to their superior sense of smell and intuitive abilities to pick up on subtle cues.
A cat’s sense of smell is approximately 14 times stronger than a human’s. Their heightened olfactory abilities allow them to detect very faint odors and chemical changes in the body that we are oblivious too. Even diseases like cancer emit chemical signals that cats can pick up on, sometimes very early on.
Cats also seem to have an uncanny sixth sense that allows them to perceive when something is wrong with their human companion. There are countless anecdotal reports of cats alerting owners to medical emergencies, and even predicting events like seizures and diabetic episodes. While not scientifically proven, many believe cats intuitively understand when we are unwell.
Additionally, cats are very observant of human behavior and energy levels. Subtle changes in appearance, posture, and activity that humans may not notice can tip a cat off that their human is not feeling normal. They seem to be able to detect subtle physical and behavioral cues we don’t perceive.
While the exact mechanisms are still somewhat mysterious, most experts agree cats have an impressive ability to sense illness in humans. Their finely tuned noses, intuition, and perception of changes in behavior likely all play a role in how cats discern when we are unwell.
Conclusion
In summary, there is evidence that cats may be able to detect certain illnesses and medical conditions in humans. Cats have shown the ability to detect cancer, seizures, low blood pressure, diabetic episodes, pregnancy, and infections through changes in behavior around affected individuals. While the mechanisms behind this are still being researched, theories suggest cats may be responding to subtle changes in human biochemistry that signal illness. However, more research is still needed to fully understand if and how cats are able to detect these conditions. The evidence so far suggests cats can sometimes alert owners to medical problems through their sensitivity and close bonds with humans. But cats should not replace medical care, and any unusual behavior warrants a visit to the doctor. Though intriguing, the extent and reliability of cats’ detection abilities requires further study.