The Stinky Truth: Can My Dog's Diet Be Making Them Smell Bad?
The idea of “doggy smell” isn’t exactly foreign to dog parents. Whether they’ve been digging in the dirt or playing in a puddle, it’s all part of sharing our homes with our furry friends. But sometimes even that familiar scent takes a sharp and unpleasant turn. That unusual or strong “off” smell, whether it’s coming from their breath, their skin, or… the other end, may be more than just a minor annoyance. It could be a sign that something isn’t quite right.
Your first instinct may be to check their ears, their teeth, and maybe even the backyard to search for things they may have gotten into. However, we often overlook the most critical place we should investigate: the dog bowl.
Your dog’s food is the fuel that keeps them going, directly impacting everything from their gut health to their skin and coat condition. That means it’s also possible their food could be contributing to the recent (and likely unwanted) change.
Keep reading to learn how your dog’s diet can directly and indirectly contribute to body odor, excessive gas, or foul breath. Plus, I’ll provide you with some actionable tips to help address and reduce that unwelcome odor, allowing your pup to get back to being their best (and best-smelling) self.
How Can Your Dog’s Diet Cause an “Off” Smell?
The idea that your dog’s diet can have an impact on their overall well-being makes sense, at its root. But how exactly can your dog’s diet change how they smell? When we discuss odors directly, we’re primarily referring to the digestive system. If a dog’s gut isn’t happy, it often lets you know through smell. But that’s not the only reason. Here are a few possible explanations:
Gastrointestinal Distress & Excess Gas
Perhaps the most common complaint is the presence of foul-smelling gas. I know, our dogs have had their fair share of stinky farts. While some gas is normal, excessive or unusually foul odors can be a sign of digestive problems. This often boils down to food intolerances or sensitivities.
Dogs, much like people, can struggle to properly break down certain ingredients in their food. Common culprits include specific protein sources (such as beef or chicken, especially if the dog has developed a sensitivity over time), certain grains (like wheat or corn), soy, or dairy products. When the dog’s small intestine can’t fully digest these ingredients, the undigested material travels to the large intestine, where bacteria rapidly ferment it. It is this fermentation process that is responsible for the rotten-egg odor.
Similarly, diets containing high fiber or hard-to-digest ingredients (such as low-quality fillers or certain complex carbs) can increase gas production because they essentially act as food for bacteria in the lower gut.
Another common culprit is a sudden change of diet. When dogs switch to a new food, it often takes a little time for their digestive system to adjust, leading to a period of increased gas. Sudden diet changes are even more challenging, disrupting the delicate balance of the gut microbiome and causing a temporary period of chaos (and unpleasant odor).
Halitosis (Bad Breath)
While bad breath in dogs is generally caused by dental problems, it’s important to note that your dog’s diet also plays a role in their dental health.
When dogs eat soft, starchy, or high-carb foods, these particles easily get stuck on their teeth. This provides a feast for bacteria in the mouth. Over time, this collection of food particles leads to plaque and tartar buildup, eventually resulting in periodontal disease. The bacteria and infections present in gum disease are a major, often rotten, source of unpleasant smells from the mouth. Simply put, their diet fuels the bacteria that cause dental decay.
Less commonly, strong breath odors may be related to the diet itself. For example, when a dog ingests highly concentrated fish oils or strong-smelling foods.
In more severe cases of digestive troubles, the odors may actually be traveling from the stomach itself due to issues such as acid reflux or chronic indigestion. Other noticeable signs, like regurgitation or excessive lip-licking, often accompany these conditions.
Anal Gland Issues
A strong, distinct fishy odor is a classic sign of issues with the anal glands, the two small sacs near the rectum. These little sacs naturally secrete a strong-smelling fluid when your dog does their “business,” triggered by the movement of firm, properly-formed stool putting the right amount of pressure on them.
If a dog’s diet is lacking sources of quality fiber or is highly irregular, the resulting stools may be too soft, small, or mushy. This prevents the necessary pressure on the anal glands, leading to them becoming full, impacted, or even infected. When a dog strains, scoots, or a full gland leaks, the resulting odor is unmistakable and is a clear sign that their diet needs to be adjusted to improve their stool quality.
Allergic Reactions & Skin Irritation
One of the most common diet-related skin problems is the irritation caused by food-related allergic reactions or sensitivities. When a dog’s immune system reacts to a protein or other ingredient in their food, it can trigger inflammation in the skin, especially the skin located on the paws, ears, and belly. This irritation creates the “itch-scratch-odor” cycle.
What does that mean? As the dog scratches and licks the inflamed area, it compromises the natural skin barrier, creating a warm, moist environment that encourages the overgrowth of yeast that naturally lives on the skin. This excessive growth of yeast is often associated with a musty, sweet odor that can be compared to the smell of corn chips.
Here’s a quick breakdown of that cycle in action:
- Allergen Ingestion: A protein (like chicken or beef) triggers an immune response.
- Inflammation & Itching: The skin becomes red, irritated, and extremely itchy.
- Licking & Scratching: The dog damages the skin’s protective barrier trying to relieve the itch.
- Yeast Overgrowth: The damaged, moist skin encourages yeast growth, causing the signature odor, often accompanied by redness, darkening, or thick “elephant” skin.
If the skin breakdown is severe, secondary bacterial infections can also take hold. This can lead to much stronger, sometimes foul or rancid odors that require veterinary attention to clear up.
Poor Coat Health
The state of your dog’s coat (and its smell) is heavily dependent on the fats and oils they consume. You can boost the health of your dog’s skin and coat by providing the right balance of Omega-3 and Omega-6 fatty acids, which support and maintain a healthy, resilient skin barrier.
However, if a dog’s diet only contains poor-quality fats or is improperly stored, those fats can become oxidized or rancid. When the box tries to process these low-quality fats and secretes them through glands in the skin, it can then create an oily, unpleasant smell.
In other cases, the skin may be reacting to a dietary deficiency or inflammation by overproducing sebum, the natural oil that helps waterproof the coat. An overly greasy or oily coat traps environmental dirt and bacteria much more easily, which can quickly lead to a strong, lingering body odor that no amount of simple bathing can truly fix.
Potential Kidney Connections
Finally, while less common and much more serious, diet-related issues can lead to bad breath that indicates a much more severe, systemic problem. For example, diets that place excess stress on the kidneys, or simply poor overall hydration, can contribute to significant medical issues.
In cases of severe, uncontrolled kidney disease, the body struggles to eliminate toxins. This can result in a distinct, pungent, ammonia or urine-like odor on the breath. This smell is not an issue of poor digestion, but rather a sign that the body’s toxin filtration system is failing, which is a life-threatening medical emergency.
When to Be Concerned and See A Vet
It’s easy to dismiss a faint smell as just “doggy breath” or a bit of gas. Still, as loving dog parents, we must recognize the difference between normal daily odors and a signal of a more serious, underlying health concern. A general rule of thumb is: if a strong, unusual odor persists despite regular grooming and teeth cleaning, or if it’s accompanied by other signs of trouble, such as physical symptoms of illness or changes in behavior, it’s time to contact your veterinarian.
Red flags to watch out for include:
- Sudden, intense, or severe odor with no clear explanation
- Ammonia or urine smell on the breath
- Sweet or fruity smell on the breath
- Persistent fishy/foul smell
- Excessive licking or scratching, especially in areas of concern like the rear area
- Extensive redness, hair loss, skin thickening, or a visible greasy discharge
Tips for Addressing and Reducing the “Stink”
The good news is that for many diet-related smells, you have the power to make changes in your kitchen that can significantly reduce or even eliminate the problem. By being thoughtful about what goes into your dog’s bowl, you can often restore balance to your dog’s gut and skin.
Feed a High-Quality Diet for Digestive Health
The foundation of a good-smelling dog starts with easy, complete digestion. To accomplish this, consider what you’re feeding (including food and treats) and how to make positive changes successfully.
Look beyond the marketing terms on the bag. Focus on highly digestible ingredients that provide maximum nutritional value with minimal waste. If you’re unsure how to select the best possible food, you can contact your veterinarian or a canine nutritionist for advice.
For dogs with sensitivities, exploring a limited-ingredient diet with a novel protein (one your dog hasn’t eaten before, like venison or duck) can help you avoid common allergens that often lead to skin inflammation and yeast overgrowth.
If you decide to switch your dog’s food, never do it abruptly. A slow transition, taking 7 to 10 days, can help to minimize gut upset, gas, and diarrhea. Mix the new food in with the old food, starting with just a small amount of the new option and slowly increasing it over time. This will allow the gut bacteria to adjust to the new ingredients.
Consider adding probiotics and prebiotics to your dog’s meal. Probiotics are the beneficial bacteria that help balance the gut, directly reducing the population of odor-causing, gas-producing bacteria. Prebiotics are the specialized fibers that feed the probiotics. Adding a quality probiotic supplement can significantly help reduce gas, optimize the digestive system, and support the immune system.
Slow Down Feeding
Do you have a speedy eater? Eating too quickly can contribute to excess gas by increasing the amount of air your dog is swallowing as they eat. Luckily, simply slowing down mealtime can work wonders! Consider using a puzzle feeder, a slow-feeder bowl, or a snuffle mat to encourage chewing and reduce air intake, making mealtimes a fun activity rather than a quick gulp.
Prioritize Dental Hygiene
If the smell comes from the mouth, addressing your dog’s diet alone may not be enough to resolve the issue, as it won’t reverse existing dental disease. Instead, you will need to focus on improving their dental and oral care. Regular tooth brushing with dog-specific toothpaste, offering dental chews and toys between brushing sessions, and scheduling professional dental cleanings as recommended by your veterinarian are all key steps in combating bad breath caused by plaque and tartar.
Consider Anal Gland Support
If the issue is that infamous fishy anal gland smell, you need to address the root of the problem. To address the immediate problem, you may need to bring your dog to your veterinarian to have the anal glands manually expressed. In some cases, this may be needed periodically moving forward.
To address ongoing anal gland issues, the goal is firm, bulky stools that naturally press on and empty the glands. You can support this by adding a small, consistent amount of a natural fiber source, such as a tablespoon of plain pumpkin puree (not pumpkin pie filling) or a psyllium husk supplement to their daily meal. This bulk helps ensure the glands are expressed properly with every bathroom break.
Incorporate Omega Fatty Acids to Support Skin and Coat Health
The most powerful dietary tool against inflammation in the skin (and the resulting odor) is the strategic use of high-quality Omega-3 fatty acids (especially EPA and DHA), often sourced from fish or krill oils. These essential fats work from the inside out to reduce skin inflammation, minimize the itch-scratch cycle, and help the skin barrier function properly, making it harder for yeast and bacteria to take hold.
Popular ways to add Omega-3 fatty acids to your dog’s daily routine include adding fish oil to their meals or providing them with a high-quality Omega-3 supplement.
Routine and Proper Grooming
While dietary changes address the root cause, regular grooming is necessary to manage any surface odor. Bathe your dog with a gentle, non-stripping dog shampoo appropriate for their skin type to wash away excess oils, environmental allergens, and surface yeast/bacteria. For dogs prone to yeast infections on their paws or ears, wiping them down and ensuring they are thoroughly dried after walks or baths can help prevent the moist conditions that allow odor-causing microbes to thrive.
Solving the Stink from the Inside Out
A persistent, unusual smell is a sign that demands your attention (and not just a quick fix, either). Your dog’s diet can directly influence the frequency and pungency of gas, the quality of stool needed for healthy anal gland expression, and how food sensitivities can trigger inflammation, leading to yeast overgrowth. While bathing your pup can offer quick relief, lasting odor control will require changes to your dog’s diet.
By choosing high-quality digestible foods and focusing on the right support and supplementation, you can tackle the root causes of discomfort and that unpleasant smell.
Remember, your veterinarian is your partner in your dog’s care team, especially if that smell is accompanied by lethargy, excessive licking, or an alarming smell like ammonia or a sweet scent. These situations warrant a vet checkup and medical help.
Prioritizing good nutrition isn’t just about feeding your dog; it's the most loving and proactive step you can take to ensure they smell fresh and are healthy from the inside out.
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Britt Kascjak is a proud pet mom, sharing her heart (and her home) with her “pack” which includes her husband John, their 2 dogs – Lucifer and Willow – and their 3 cats – Pippen, Jinx, and Theia. She has been active in the animal rescue community for over 15 years, volunteering, fostering and advocating for organizations across Canada and the US. In her free time, she enjoys traveling around the country camping, hiking, and canoeing with her pets.
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