It’s hard to say what odors humans emit when they are happy. Maybe a fresh bath and chocolate chip cookies? That would seem right to us humans.

Dogs, however, are more sensitive, and they can tell what’s going on with us by how we smell, with or without cookies. Even if we’re dirty and smell like kale, a dog nose could pick up on happiness. They can also detect fear with ease.

What every dog owner has suspected all along has scientific proof. In 2017, a researcher confirmed that golden retrievers reacted to fear and happiness odors on their owner, a stranger, and someone who dispensed sweat samples.

Not surprisingly, when the dogs’ owners were stressed, so were the dogs. Their heart rates rose and their behavior changed.

A dog’s ability to smell our physical condition is well established. That’s the basis behind diabetic alert dogs that are trained to warn their owners that their insulin levels are too high or low. Numerous owners can confirm that their dogs know when they are sick, sometimes even before we admit to it.

But until now, there was no scientific proof that dogs could detect emotions by smell. While dogs do recognize facial expressions and gestures that signal our moods, smell brings the dog-human relationship to a whole new dimension.

The dog-human relationship is already an oddity in the natural world.  For years, people who remained skeptical doubted that dogs had real love or loyalty to their humans. It was more likely a win-win bargain involving shelter and food the disbelievers thought.

And yet, it was hard to explain why a dog would run into danger to help a human, especially the human that was “theirs.” Experiments at Wright State University found that dogs were more emotionally bonded to their humans than they were to other dogs, even when those other dogs had been paired and housed with their littermates for years. When these dogs were separated from their dog pal and their caretaker, they became stressed. But the surprise was that they were more comforted by their familiar human caretaker than they were when their littermate was brought back.

These are lonely times. That’s a general statement that transcends this year. More than 35 million Americans, about 28% of us, live alone. Many loners are older Americans, who may not even see others routinely by going to work each day and lack company in the house from dinner onwards. More recently, millions of us are forced to be socially distant, maybe even quarantined, for our health.

A dog could help. So could a cat, even if there is no proof cats can smell your joy. They are willing to snuggle when you feel bad, though. Reports from animal shelters indicate that they are eager to help people adopt cats and dogs as they struggle to keep enough staff and volunteers on board.

It’s not a bad feeling to know something wants you to feel better and know how you’re doing.