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Why does my dog eat worms?

Why does my dog eat worms?

Dogs eat some strange things. Seeing your dog eat a worm can be disconcerting. In addition to the gross-out factor, you may be concerned about the effect on your dog’s health. Animal behaviorists are still studying why dogs do certain things. In fact, why dogs eat grass is still debated. Some researchers believe they simply enjoy the taste, while others believe they eat grass to obtain a nutrient that is missing in their diet. There are several reasons why your dog may enjoy munching on the occasional worm. 

Why does my dog eat worms?

If you’ve seen your dog slurp up one of these wiggly ground dwellers, your first thought is likely “Why?”. You give them plenty of food. Toys. You may even be shocked by your dog’s behavior. 


Pica is a condition that can affect dogs and humans. Pica is defined as compulsively eating non-food items. Dogs with pica can eat a wide variety of things, including plastic, paper, poop, and worms. Pica can be caused by a medical issue or it can be behavioral. Some dogs with pica are interested in a specific non-food item, while others will eat all manner of inappropriate items. 

Generally, pica doesn’t occur in puppies. Puppies will naturally eat non-food items because they are learning what is food and what isn’t. The main symptom of pica is eating non-food items. However, some dogs are secretive about their endeavors. If your dog has frequent stomach upset, lethargy, or lack of appetite, pica could be the culprit. 

Pica can be caused by a range of medical conditions, including nutritional deficiencies, endocrine disease, parasites, and liver disease. Behavioral causes of pica include stress, anxiety, and boredom. 


Curiosity is a common cause of eating worms in puppies, but it can occur in adult dogs as well. If your dog has never tried worm, they may simply want to know if it’s food or not. The only way for them to find out is to eat one and see. 

Hunting Instinct

Some dogs have a stronger hunting instinct than others. It’s possible that some dogs see a writhing worm as prey, and eating it is simply instinctual for them. 

They Find Them Tasty

Certain worms are considered a delicacy in some parts of the world, while other cultures can’t imagine snacking on one unless they were starving. Just like people, dogs will have varied tastes. Some dogs may simply enjoy the protein-filled snack, to the utter horror of their owner. 

How to stop my dog from eating worms?

How to stop your dog from eating worms will depend on why they are eating worms. Regardless of the cause, there are a few basics that can help. 

First, admonish them when you spot them going after a worm. This requires consistency and a watchful eye. You’ll need to catch them and say “No” or whatever command you’ve chosen to stop unwanted behavior each time you see them attempting to eat a worm. If they spot a worm and don’t attempt to eat it, praise them. 

You may need to keep your dog inside unless you can carefully supervise for a period of time. You can also avoid areas where worms are plentiful. Worms tend to appear above ground when it rains, so be extra watchful if you let your dog out after a rain. However, be aware that dogs can also dig into the ground to find worms. 


If you think pica is the cause, you’ll need to determine if it’s medical or behavioral. Your vet is the best person to figure this out, because they can check for medical causes. You’ll also need to evaluate your pet’s diet to ensure that there are no nutritional deficits. 

If it’s behavioral, try to get to the root cause. Is your dog bored because they are home alone during the day? Are they experiencing stress or anxiety? In some cases, they may need anti-anxiety medications temporarily. However, if you can identify the reason for their anxiety, you may be able to eliminate it. 


If your dog is eating worms out of curiosity, they should soon tire of it. Keep them occupied outdoors and give them other ways to satisfy their curiosity. Consider walks in new locations to provide new sights and smells. Get them a puzzle toy to stimulate their brain. 

Hunting Instinct

If your dog is eating worms out of hunting instinct, getting them to stop can prove to be challenging. Redirect them when they spot a worm. A loved toy is a great way to divert their attention and can give them a similar feeling of hunting or battling prey. 

Tasty Snack

If your dog enjoys the taste of worms, try to keep them occupied when they are outside. You can try giving them a favorite snack to satisfy their taste buds. 

Are worms harmful to a dog?

When humans eat worms, they have a few ways to avoid the potential risks. They can be gutted, which removes potentially contaminated soil and parasites from the worm. They can be boiled or fried, which kills parasites and bacteria. They can also be fed a diet of cornmeal for a few days. This allows their system to purge. This flushes out potential toxins. However, they may still harbor parasites. Dogs don’t have any of these techniques at their disposal. When they eat a worm, it’s usually fresh with potential contaminants intact. 

The good news is that most worms themselves are not harmful to your dog. The bad news is that they can carry bacteria or parasites that are dangerous to your furry friend. Worms eat soil. They then excrete it in a better condition than they ingested it. The problem is that the soil can contain some things that can jeopardize your dog’s health. These include fungi, pesticides, bacteria, and parasites. 


This is the biggest concern when a dog eats worms. Roundworms are the most common. These are the worms that often affect puppies. If the worm has roundworm eggs, when your dog ingests the worm the eggs can hatch and make their home in its system. Roundworms can also be passed on to humans. If you are concerned about roundworms, check your dog’s poop. If you notice small white worms, your dog has roundworms. Other types of parasites including hookworms and whipworms can also be found in soil, and may be transmitted by eating worms. 

The giant kidney worm is rare, but can also be contracted from eating worms. They attack the abdomen and kidneys. Ultimately, they destroy the kidneys. Typically, only one kidney is affected. If both kidneys are affected, death usually occurs due to kidney failure. 


Bacteria found in the soil can give your dog a stomach ache. Vomiting and diarrhea can occur. It typically lasts from a few hours to a few days and doesn’t pose long-term health risks. 

Pesticides and Chemicals

Pesticides and chemicals found in the soil can become concentrated in the worm. These can be harmful, but your dog would have to eat a lot of worms to get enough exposure for negative effects. It’s rare that a dog suffers ill effects due to this, but it is a possibility, particularly over an extended worm-eating time period. 

What to do if my dog ate a worm?

If your dog ate a worm, the best thing to do is to monitor them. Check their stool for signs of roundworms. Watch for symptoms of stomach upset or lethargy. If you are concerned, you can take them to the vet. Your vet will check them for parasites and bacteria. In most cases, eating an occasional worm doesn’t cause any harm. 

In addition to teaching your dog not to eat worms, make sure they are up to date on their veterinary visits. This can allow your vet to check for parasites and administer preventatives.