Most dog owners are familiar with their pups’ enthusiasm for food, whether it’s begging for a bite, scavenging crumbs or munching on grass. It seems like dogs can eat almost anything — but should they? 

Research suggests that, with a few key exceptions, dogs have pretty flexible diets. In fact, their ability to eat a wide variety of foods likely played a major role in making dogs the human companions they are today. 

However, just because a food doesn’t hurt your pup, doesn’t necessarily mean it’s beneficial.

Similar to humans, dogs need nutritionally balanced diets – not only for healthy growth and development, but also for regulating their behaviors. 

So, what should you feed your dog for optimal health? And what should you avoid to prevent harmful or even fatal outcomes?

Dogs and Diet Evolution

Dogs are thought to be the first mammal that humans domesticated, and their diets reflect the split from their wolf ancestors. 

Wolves began living alongside people as early as 17,000 years ago, feeding off food waste left at the outskirts of human settlements.

This exploitation of new food sources set domestication in motion; eventually, dogs adapted to eat a wider variety of foods than their strictly carnivorous ancestors.

Read More: Dogs Have Co-Evolved With Humans Like No Other Species

What Foods Are Good for Dogs?

Despite their ability to eat other foods, lean meats such as chicken, turkey and beef remain the foundation of commercial dog diets today. 

Protein Sources

Meat provides many of the proteins and fats essential to canine growth and development. Fats are particularly important for brain health and can affect cognitive performance and behavior in dogs. 

Amino acids derived from proteins are building blocks for muscles, hormones and chemicals that send messages throughout canine bodies.

Insufficient or incomplete protein consumption can manifest in dogs with weight loss, anemia, mood changes and other troubling symptoms.

Read More: What To Do If Your Pet Is Struggling With Anxiety

Veggie and Fruit Guidelines

Fruits and veggies can also be a positive addition to most dogs’ diets.

Foods like carrots, green beans, sweet potatoes and blueberries provide extra fiber and nutrients without adding too many extra calories. 

Although there is some evidence that a vegetarian or vegan diet can meet all of a dog’s nutritional needs, there is not yet sufficient long-term research to justify fully eliminating meat from your pup’s diet just yet.

Starch Adaptation

Starches, like rice and potatoes, are another ingredient commonly found in dog food. 

The ability to digest starch, which wolves cannot do, arose in early dogs during the agricultural revolution when people started eating more starchy foods.

A genetic mutation eventually led to the emergence of the AMY2B gene, which allows dogs to produce more of the enzymes needed to break down starch into usable energy. 

There is no scientific proof that starches are bad for dogs. When included as part of a balanced diet, they can help your pup feel full and energized while contributing to good gut health. 

Can Dogs Eat Human Food?

While dogs can eat certain human foods, such as those listed above, their nutritional needs and food tolerances differ from those in humans. 

Limit Table Scraps

Feeding dogs exclusively human food or incorporating excessive table scraps into their diet can cause deficiencies and imbalances in their nutritional intake.

Many foods in a typical Western diet are highly processed and contain additives, preservatives and high levels of salt or sugar, which can harm dogs in excess.

Mind the Salt and Fat

For instance, salty foods like deli meats and cheeses can contribute to kidney problems among other conditions. Consumption of fatty or fried food can potentially trigger pancreatitis, which is the inflammation of the pancreas and can lead to severe health complications.

Avoid Human Diet Trends

Experts say it is also important to not project human food intolerances onto dogs.

Trends like “grain free” diets, which are designed for people with celiac disease and other health conditions, have no real evidence of being beneficial to dogs. Research also indicates that going grain free might elevate risk of heart disease in some dogs.

Read More: Grain-Free Diets Have Been Linked to Serious Heart Problems in Dogs

What Foods Are Toxic to Dogs? 

Your dog may be your best friend, but when it comes to sharing a beer, they’re not the right companion. 

Unlike humans, dogs can’t process ethanol, the type of alcohol that humans consume. This means that even small amounts of alcohol can cause alcohol poisoning, which can lead to a coma and death in severe cases. 

Here are a number of other dangerous foods for dogs:

Onions, Leeks and Chives

Alliums, including garlic, are all toxic to dogs. That’s because when canines chew them, it releases sulfur compounds that inhibit the transport of oxygen throughout the body. Symptoms of allium poisoning include vomiting, diarrhea, abdominal pain, loss of appetite and depression.

Chocolate

Cacao contains theobromine, a compound that triggers negative reactions in a dog’s body including: stimulating the nervous system, increasing stress on the heart, relaxing breathing muscles and increasing urination. 

Caffeine

Similar to cacao, caffeine sets off a cascade of responses in canine bodies that can quickly become fatal. 

Hops

Hops contain several compounds toxic to dogs. Ingesting hops can cause “malignant hyperthermia” in which body temperature quickly rises and muscles contract. 

Macadamia Nuts and Walnuts

Macadamia nuts and walnuts can cause weakness, tremors and other neurological issues in dogs. Yet, researchers are still unsure exactly why these nuts make dogs so sick. 

Unbaked dough

Unbaked dough that contains yeast is unlikely to be fatal to dogs. However, if enough is ingested, dough can expand in the stomach and cause uncomfortable, potentially dangerous blockages. 

Xylitol

Xylitol, an artificial sweetener commonly found in gum and sugar-free products, promotes insulin release, which causes blood sugar to plummet and can ultimately result in death. 

This list is meant to be a guide, so if your dog consumes unfamiliar or potentially harmful foods, the safest route is to contact your veterinarian immediately for professional advice.

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