A bit of wind is normal. When it becomes constant, or bad enough to clear the room, it's nearly always about what your dog eats and how it eats it. Here's where the gas comes from, the most common causes, what really helps and the signs you shouldn't ignore.
In short
Dog flatulence comes from air swallowed while eating and from gas made by bacteria in the large intestine as they ferment what wasn't digested; the smell is mostly hydrogen sulphide. The most common causes are switching food too fast, table scraps, milk and dairy, raiding the bin and gulping meals. In most cases it's enough to switch food over 7-10 days, cut out scraps and dairy and give smaller meals. A swollen, hard belly with retching that brings nothing up is an emergency; gas with diarrhoea, vomiting or weight loss needs a vet.
For two reasons: swallowed air and fermentation in the gut. Part of the gas is air your dog swallows while eating or breathing. It happens most to fast eaters and flat-faced dogs: in a 2024 study of 120 dogs seen at two university veterinary hospitals, excessive air swallowing was far more common in brachycephalic breeds such as bulldogs and pugs (46% vs 14%). The rest of the gas is made by bacteria in the large intestine as they ferment what wasn't digested earlier.
The smell depends on what the gas is made of, not on how much there is. A study that measured dogs' gas with a sensor found that the strength of the smell tracked hydrogen sulphide, a gas bacteria produce from compounds that contain sulphur, such as some proteins. That's why a dog can produce a few dreadful farts, or lots of almost odourless ones.
In studies on dogs, less than you'd read. In University of Kentucky research published in 2006, diets based on soybean meal, regular or with fewer fermentable sugars, produced no more flatulence than a diet with poultry meal. The soy was slightly less digestible, but the gas was the same.
More than any single ingredient, what matters is how well the food is digested and how used to it your dog is. Every dog is different, though: if a particular food always causes trouble, note it down and tell your vet.
Yes, in studies digestibility is higher. At the University of Illinois, 12 dogs ate in turn an extruded kibble, a refrigerated fresh food and two gently cooked foods made with human-grade ingredients. On kibble the dogs had to eat more to keep their weight and produced 1.5 to 2.9 times more faeces, because a bigger share of the food passed through undigested.
Less residue reaching the large intestine means less material left to ferment: a good reason to choose a highly digestible food. To be fair, these studies measured digestion and stools, not gas directly.
On gas there is only one study, to be read with caution: in 2021, 31 dogs switched from kibble to a cooked fresh food and after 28 days one owner in three (32%) noticed less flatulence, 6% noticed more and the rest no difference. There was no control group, the owners did the judging and the study was run by the company that made the food.
They may help with the smell, much less with the amount. In a study of 8 dogs, a treat with activated charcoal, yucca and zinc acetate didn't change how often the dogs passed gas, but cut the share of episodes with a bad or unbearable smell by 86%. It's a small study, and these products should only be used with your vet's advice.
For probiotics the evidence is weak: a systematic review of studies in dogs found a very limited effect on acute gut upsets and no clear benefit in chronic ones, where diet remains the main lever.
When the belly swells quickly and your dog tries to vomit but nothing comes up. It may be gastric dilatation-volvulus (bloat), an emergency that mostly affects large and giant deep-chested dogs, such as Great Danes, Weimaraners, St Bernards and setters. Other signs: an anxious look or staring at the belly, heavy drooling, panting, weakness. Go to an emergency vet immediately, even at night: it gets worse fast.
Outside these cases, see your vet if the gas increases suddenly and comes with diarrhoea, vomiting, blood in the stools, loss of appetite or weight loss.
Our recipes are made to be easy to digest: real meat as the first ingredient (52% to 67%), a single animal protein per recipe, a few vegetables and a vitamin and mineral supplement, steam-cooked and sterilised in their own pouch. Few ingredients also means you always know what your dog is eating.
If you switch to Pappa Fresh, do it over 7-10 days as described above: in the first days a bit more gas is normal while the gut adjusts. If it hasn't settled after two or three weeks, talk to your vet.
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Usually because of something it ate: a food change that was too fast, scraps, dairy or the bin. The strong smell comes mostly from hydrogen sulphide produced by gut bacteria. If it lasts more than a few days or comes with diarrhoea or vomiting, talk to your vet.
Yes, it's common in the first days: the gut bacteria have to adapt to the new food. That's why the switch should take 7-10 days, increasing the new food little by little. If the gas hasn't eased after two or three weeks, talk to your vet.
Flat-faced breeds such as bulldogs, pugs and boxers, which swallow more air; dogs that eat very fast; and dogs whose food changes often or who get scraps. In a study of English Bulldogs from dog shows, burping and flatulence were more frequent than in healthy reference dogs.
No food has been shown in controlled trials to prevent gas. In one small study without a control group, a third of owners noticed less gas four weeks after switching from kibble to a cooked fresh food. What helps for sure is a highly digestible, complete food your dog is used to, introduced over 7-10 days, with no scraps or dairy on the side. If the gas persists for weeks with a given food, your vet may suggest trying a different protein.
Straight away if the belly swells quickly and turns hard, if your dog retches without bringing anything up, drools and is restless: it may be gastric dilatation-volvulus, an emergency mostly in large deep-chested dogs.
Written by the Pappa Fresh editorial team from published veterinary studies (see sources). Not a substitute for your vet's advice.
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