Can Cats and Dogs Sense Illness in Their Owners?

You’ve probably heard stories of pets that have alerted their owners to illnesses such as cancer but is there any scientific proof that our furry friends have a special ability to sense when you are ill?

Can Animals Be Trained to Detect Illness?

In some studies, dogs have shown potential for detecting chemicals released by malignant tumours, through urine, stool and breath samples.

In 2004, a study revealed that dogs had an ability to sense bladder cancer via urine samples. After this promising test, more research was carried out in the US and Japan and the results were astounding. Dogs in California were trained to use breath samples from cancer patients and recorded an 88 per cent success rate for breast cancer and 97 per cent for lung cancer.  In Japan, the results were even better. The 98 per cent success rate for colorectal cancer was thought to be slightly more accurate than standard tests to diagnose this particular form of cancer.

These dogs were trained in how to detect various forms of cancer but on a much less scientific note, various pet owners have told how their pet has sensed cancers that had not been diagnosed at this point and in many cases, they were completely unaware of their illness.

The definite potential for using dogs in detecting cancer will be tested further, after the Medical Detection Dogs charity announced plans for a widespread clinical study in which 9 dogs will test samples from 3000 patients. They will specifically be looking to detect bladder, kidney and prostate cancer.

There has been a lot of focus on the ability of dogs to sniff out cancer but cats have also been able to do this. In America, cats have apparently been able to alert their owners to lung cancer and breast cancer, and here in the UK, there have been similar stories.

How It Works

How do some pets pick up on cancers with just the power of smell? Experts assume that pets may be able to pick up on subtle scent changes, which are not perceptible to us. Cancerous tissue is believed to smell slightly differently to normal, healthy tissue, for example. With their dramatically enhanced sense of smell, dogs are much better equipped to notice this compared to humans and the studies that have been conducted to date have taken advantage of this to teach dogs to sniff out particular scent changes.

Cats also have a keen sense of smell, and may be able to pick up on the same kind of scent changes as dogs.

Detection is only part of the story, of course. In almost all of the stories told by owners, dogs and cats have found ways to let them know that something is wrong. This has often involved pawing at particular areas to highlight lumps to be noticed by their owner, for example.