By Dana Poblete for Thrive Market From Mashable

Consider the case of the shark and the remora. Anyone who’s ever watched Shark Week has seen their mutually beneficial relationship play out: The remora fish attaches itself to its host and gets a healthy meal of parasites while the shark gets clean as a whistle. But this dynamic duo ain’t got nothing on humans and pets.

Dogs, cats, and humans have been able to evolve together for good reason. Humans and their pets have the ultimate symbiotic relationship. The simple task of feeding a pet and looking out for their health and safety is a small price to pay for all the good they can do for us. Here are six ways four-legged friends bring good health and happiness to their humans, simply by being themselves.

A study in the Journal of Psychosomatic Medicine showed that pets can help decrease blood pressure and stress in an individual, even better than a significant other or a friend can. Researchers believe this is because there is no fear of judgement or criticism from a pet; perhaps even the most supportive spouse or friend is no match for the unconditional love of a dog or cat.

Disease detectives

With their keen sense of smell, some dogs can be trained to detect low blood sugar in diabetics just by smelling their breath. Canines are currently also being trained to identify the odor of volatile organic compounds (VOCs) that may indicate cancer. So far, dogs have been able to detect melanoma, bladder, lung, prostate, breast, and ovarian cancers.

Stop sniffles

No matter how irresistible it is to snuggle a cute little furball, sometimes it’s just not worth it if their dander causes debilitating symptoms like scratchy eyes, a stuffy nose, and relentless sneezing. But ironically, early exposure to pets can actually stop allergies from developing! Kids exposed to animals when they’re very young build a tolerance and prevent respiratory issues like allergies and asthma in the future.

Giving a dog a good petting can release oxytocin in the human’s body, lowering blood pressure and cortisol. This means less stress, and also less belly fat, which is correlated to cortisol levels. Oxytocin is also released when dogs and their owners look into each others’ eyes, like a mother and baby. One study showed both dogs’ and their owners’ oxytocin levels go through the roof after making puppy dog eyes at each other.

Social butterflies

People who own dogs — and walk them — are in better shape and are less likely to be obese than people who don’t, since exercise is built in to their routines. In turn, this can also reduce the risk of heart disease as well as other diseases linked to a sedentary lifestyle, including diabetes, hypertension, and osteoporosis. Heading outside with a pup in tow also means an increased absorption of vitamin D from sunshine.

Quality control

A puppy or kitten waiting to be fed at home can be enough to inspire some people to think twice about engaging in risky behavior. This is one way to increase odds of longevity. But caring for a pet can also heighten a person’s self worth and sense of purpose.

It’s a simple truth: Dogs and cats can improve quality of life all around. They won’t ask for much in return, but kind gestures in the form of healthy, tasty food and fun toys to keep them active can ensure a pet friend will keep living the dream for a long, long time.

IMAGES:
DALE SPARTAS/CORBIS
IMAGE: MASHABLE COMPOSITE/OLEH SLOBODENIUK/CORBIS

This article originally published at Thrive Market here

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