The idea that dogs eat grass to soothe an upset tummy or make themselves throw up has been regurgitated more than chewed-up grass itself. A research study published in 2010 in the journal Applied Animal Behaviour Science found that dogs were actually less likely to consume grass when experiencing gastrointestinal upset. This makes more sense, considering dogs cannot digest grass and thus would not benefit much from its ingestion.

Experts at VCA Animal Hospitals have theorized that dogs eat grass because they are curious, hungry, bored, or seeking attention from their owner—in other words, it is normal behavior. Wolf scat analyses have found grass in significant amounts, suggesting foraging for plant material is consistent with instinctive behavior.

Considering how many foul-smelling things dogs are willing to put in their mouths, it is not necessarily surprising when Fido's kisses are a little less tolerable than usual. Persistent bad breath can be a sign of underlying health issues, according to the AKC. Interestingly, dog saliva is more alkaline than human saliva, making it less hospitable to bad-smelling bacteria.

Just like humans, poor oral hygiene is the leading culprit of bad breath and can be mitigated by increasing brushing. Accompanied by symptoms like changes in appetite or excretion, though, bad breath may also signify liver or kidney disease.

Dogs do groom themselves by licking, but excessive licking is often a sign of skin irritation or discomfort, which can have an array of causes and lead to bigger problems. Dogs are instinctively motivated to lick irritated spots and wounds to clear them of potential pathogens and promote healing. While their saliva does contain healing properties, the action presents a high chance of transmitting bacteria into the wound—so licking is generally not recommended as a treatment regimen.

Absent of any obvious causes of skin distress, such as redness or fleas, allergies may be the culprit of excessive licking. According to the AAHA, about 1 in 10 dogs have skin allergies, the most common allergic reaction in dogs.

Dogs do fall under the order Carnivora, but that does not mean they exclusively eat meat; even pandas, which eat bamboo almost exclusively, are technically carnivores using that criterion.

It is true, however, that their dietary habits derive from their ancestral roots—and wolves eat plenty of plant material too. One major distinction between the digestive systems of wolves and dogs is that dogs can produce amylase, which is used to break down grains in the digestive system. Furthermore, according to the AAHA, meat- and grain-based ingredients are equally digestible by dogs.

It is one of the sadder facts of life that dogs have much shorter life spans than their owners, but it is not quite as simple as one year for every seven human years. The start of this aphorism is uncertain, but it likely originated during a time when the average human lived to be around 70 years old and the average dog was 10 years old.

In fact, the presumed life span of a dog varies significantly depending on its breed and size and is a bit more complex than multiplying by seven. According to the AAHA, a dog's first full year of life is akin to the developmental state of a 15-year-old human. The second year adds about nine human years. From there, the aging pace changes by size, with smaller dogs vastly outliving larger dogs. Regardless, quality time always trumps quantity of time—so maybe make that extra trip to the dog park.

Story editing by Carren Jao. Copy editing by Paris Close.