Just last year, Medical News Today reported on a study that showed that owning a dog reduces a person’s risk of premature death by up to a third.
Also, researchers at the University of Harvard in Cambridge, MA, suggest that dog owners have a lower risk of heart disease.
Why is that? It is difficult to establish a causal relationship between owning a dog and enjoying better health.
However, the benefits may appear thanks to a series of factors related to lifestyle adjustments that people tend to make after they decide to adopt a canine friend.
The most prominent such lifestyle factor is physical activity. There is no way around it: if you own a dog, you have to commit to twice daily walks — and sometimes even more.
According to a Paper Trusted Source published in The Journal of Physical Activity and Health, dog owners are more likely to walk for leisure purposes than both non-pet owners and people who own pet cats.
The results were based on studying a cohort of 41,514 participants from California, some of whom owned dogs, some of whom owned cats, and some of whom did not have any pets.
Moreover, several recent studies — including one from the University of Missouri in Columbia and another from Glasgow Caledonian University in the United Kingdom — found that adults aged 60 and over enjoy better health thanks to the “enforced” exercise they get by walking their dogs.
Dogs can strengthen our health not just as we grow older, but also much, much earlier than that: before we are even born.
Research published last year suggests that children who were exposed to dogs while still in the womb — as their mothers spent time around dogs during pregnancy — had a lower risk of developing eczema in early childhood.
Also, children exposed to certain bacteria carried by dogs also experienced a reduction of asthma symptoms, the researchers noted.
“Dogs make people feel good”
Perhaps the most intuitive benefit of sharing your life and home with a canine friend is that dogs give you “feel-good vibes” almost instantly.
Dogs are often used as therapy animals because they have a calming effect on people.
It is really difficult not to cheer up, even after a hard day’s work, when you are greeted with — often vocal — enthusiasm by a friendly dog.
This, researchers explain, is due to the effect of the “love hormone” oxytocin.
“During the last decades,” write the authors of a review that featured in Frontiers in Psychology, “animal assistance in therapy, education, and care has greatly increased.”
When we interact with dogs, our oxytocin levels shoot up. Since this is the hormone largely responsible for social bonding, this hormonal “love injection” boosts our psychological well-being.
Previous studies analyzed in the review have revealed that dog owners have more positive social interactions and that the presence of canine friends makes people more trusting…and also more deserving of trust.
Moreover, dogs appear to reduce symptoms of depression and render people more resilient to stress. That is why dogs are often used as therapy animals. As researcher Brian Hare, of Duke University in Durham, NC, noted in an interview for The Washington Post:
“Dogs make people feel good, and their only job is to help people in stressful situations feel better.”
Thus, learning more about dogs’ gut microbiota and how they are affected by diet could help us understand how best to tackle our own eating habits.
Like humans, dogs can also develop some forms of cancer. Much like us, dogs can get brain tumors to similarly destructive effects, so learning which genes predispose our canine companions to gliomas may also be translated into cancer research for human patients.
Moreover, a contagious form of canine cancer could shed light on how forms of cancer found in humans have come to develop.
Dogs can also experience certain features characteristic of dementia, such as impaired problem-solving abilities.
Researchers explain that by understanding how cognitive tasks are affected in these quadrupeds, we may become better equipped to solve the riddle of dementia in the case of humans, too.
“Dogs,” notes Dr. Rosalind Arden, of the London School of Economics and Political Science in the U.K., “are one of the few animals that reproduce many of the key features of dementia.”
“[S]o,” she goes on to add, “understanding their cognitive abilities could be valuable in helping us to understand the causes of this disorder in humans and possibly test treatments for it.”
Dogs are not just incredibly loveable and often very funny friends whose antics fuel the Internet’s store of memes continuously; their company also keeps us in good physical shape. Also, their health problems — sadly but endearingly — often mirror our own.
Most of all, however, we welcome them into our lives — and have done so since time immemorial — because they instantly bring us the sort of joy and calm that we would otherwise have to work hard to obtain.
Author Dean Koontz summarized this perfectly in the memoir of his own much-loved dog:
“One of the greatest gifts we receive from dogs is the tenderness they evoke in us. […] By their delight in being with us, the reliable sunniness of their disposition, the joy they bring to playtime, the curiosity with which they embrace each new experience, dogs can melt cynicism, and sweeten the bitter heart.”
Medical detection dogs: how they could save our lives in a sniff
The term “man’s best friend” is commonly used when it comes to dogs, and it is not hard to understand why. The loyalty of a dog toward its owner is something that cannot be questioned. But in recent years, the tables have turned and humans have become more reliant on dogs than ever before – to help save lives.
According to The Humane Society of the United States, there are around 83.3 million owned dogs in the US alone, showing that America is clearly a nation of dog lovers. But do we underestimate the talent of these amazing creatures and see them purely as pets?
In recent years, organizations all over the world have looked to train dogs to detect medical conditions in humans.
Earlier this year, Medical News Today reported on research from UK charity Medical Detection Dogs(resource no longer available at www.medicaldetectiondogs.org.uk) detailing how dogs have the ability to alert their diabetic owners when their blood sugar levels are too low (hypoglycemic).
But how exactly are dogs able to detect human disease?
All in the scent
A dog has around 125 to 300 million scent glands, while a human has around 5 million scent glands. This means a dog’s sense of smell is around 1,000 to 100,000 times more sensitive than a human’s
It is a dog’s intricate sense of smell that has captured the interest of the medical world in using these animals to help detect human diseases and to help people who suffer from these diseases live a more fulfilling life.
Dogs4Diabetics is a US organization founded in 2004 that researches, trains, and places medical assistance diabetic alert dogs with insulin-dependent diabetics.
Ralph Hendrix, executive director of Dogs4Diabetics, told Medical News Today how dogs are able to detect hypoglycemia in diabetics.
“We believe all diseases have a scent associated with the diseases, due to the changes occurring within the body, with different organs expressing different chemical compounds. These scents are evident in breath and sweat,” he explained.
“Dogs have highly sensitive senses and can learn to recognize symptoms from many types of disorders. In our work, they are not taught to react to symptoms, but to scent.”
But of course, these dogs do not automatically adapt to the detection of these scents. A great deal of training goes into ensuring they acquire the correct smell to carry out their job.
Train to gain
According to Hendrix, the dogs they train must meet set criteria in order to become medical detection dogs.
“The criterion ranges from their behavior characteristics, their relationships with humans (ability to bond and willingness to please), their environment soundness, to their work ethic, motivations, response to reward, etc.”
Dogs4Diabetics use breeds that have been raised and socialized to take part in service work. The dogs they use are donated to them by Guide Dogs for the Blind of San Rafael and Canine Companions for Independence of Santa Rosa, both in California.
Hendrix says that the dogs donated to them are primarily Labrador retrievers and golden retrievers, or a mix of the two breeds.
“Other breeds may work, but these breeds are well accepted for service work because of the temperament and disposition to work with their human companions,” he told Medical News Today.
Explaining how dogs can be trained to sniff out hypoglycemia in diabetic patients, Hendrix said the dogs are trained on a scent collected from a diabetic’s breath or sweat when they are experiencing hypoglycemia:
“That dog is trained to identify the hypoglycemic scent and then is taught to discriminate the hypoglycemic scent from other attractive, but distracting, scents through a series of games and training exercises. The dogs receive positive rewards for identifying the correct scent and for their work.”
Hendrix added that it takes some time to train a dog to make the transition from “scent discrimination training” to detecting actual hypoglycemia on a diabetic in a home environment.
“All diabetics will have residual scent around from previous hypoglycemic episodes. This ‘dead’ scent lingers in their home, their clothes, their bed. The dogs have to learn to differentiate the ‘dead,’ lingering scent from the ‘live’ scent, and transition their alert to only the live scent for which they are rewarded.”
Hendrix added that the dogs also have to be trained to identify and alert on the hypoglycemic scent within different environments, such as work, at school or in the car.
“To the dog, it is simply a game with positive rewards that is played everywhere,” he added.
Hendrix explained that Dogs4Diabetics’ clients also receive extensive training, including how to respond to the dog once it alerts them that there is a problem with their blood sugars. The owner must be sure that the dog is accurate in their alert by testing their blood sugar levels with a glucometer to confirm there are any changes.
Potential for cancer detection
It is not just hypoglycemia that dogs have the ability to sniff out. Continued research is looking at the use of dogs to detect various types of cancer – named “bio-detection dogs.”
Earlier this year, Medical News Today reported on a study detailing how researchers are looking to create a breakthrough method of using dogs to detect ovarian cancer.
The researchers explained that the dogs are able to detect volatile organic compounds (VOCs), or odorants, that are altered in the early stages of ovarian cancer.
Using four trained sniffer dogs to analyze urine samples from patients who had bladder cancer, alongside healthy controls, the researchers found that the dogs’ specificity in detecting the cancer ranged from 56% to 92%.
A video from Medical Detection Dogs explaining how bio-detection dogs are able to detect scents of cancer and other diseases can be viewed below.
Previous research has also found that dogs may be able to smell volatile organic compounds from a patient’s breath sample – as these compounds may appear on the breath in the early stages of cancer.
Medical News Today
“We condition the dog to the volatile pattern of a cancer sample with the use of an audible sound, such as a clicker. The clicker is associated to something the dog enjoys. For example, a treat or toy.The clicker signals to the dog that the last behavior carried out before the click was correct and he will receive his reward. Over time, the dog learns that the click only appears as he sniffs at a cancer sample.”From this ongoing research, investigators have even started creating devices that may detect cancer by “mimicking” the sensitivity in a dog’s nose.
The Na-Nose™ – created by researchers at the Technion-Israel Institute of Technology and Alpha Szenszor, a carbon nanotube manufacturer in Boston, MA – is a device that can analyze more that 1,000 different gases in the breath in order to detect lung cancer. In clinical trials, the device has been found to have up to 95% accuracy.