How often should I change my dog's food?

There's no fixed schedule, most dogs do well staying on a suitable food for a long stretch, and changes are best made for a specific reason, such as a life stage change or a health concern, rather than on a routine.

Can changing food upset my dog's stomach?

Yes, particularly if it's done suddenly. A gradual switch over about a week to ten days, mixing the new food in gradually, is far less likely to cause loose stools or an upset stomach than swapping the bowl over all at once.

Is a more expensive dog food always better?

Not necessarily. Price doesn't directly correlate with how well a food suits your individual dog, a moderately priced complete diet that your dog does well on is a perfectly good choice, and the ingredients and your dog's response matter more than the price.

When should I speak to my vet before changing food?

If your dog has a diagnosed health condition, ongoing digestive issues, or unexplained weight change, it's worth discussing a food change with your vet first rather than switching on your own, since the right diet may depend on what's actually going on.

Should I change my dog's food?

There are genuinely good reasons to change your dog's food, a new life stage, an ongoing health issue, or a food that's stopped agreeing with them, and there are reasons that sound convincing but aren't, like chasing the latest trend or assuming more expensive automatically means better. The honest answer is that most dogs do well staying on a food that suits them, and switching should usually be a response to something specific rather than a habit.

Good reasons to change

A change in life stage is the clearest one, a puppy moving to an adult formula, or an older dog moving to a senior recipe with adjusted calorie content, is a normal and sensible switch rather than something to second-guess. Ongoing digestive upset, unexplained weight change, or a vet-diagnosed condition that needs a specific diet are also good reasons, ideally guided by your vet rather than trial and error alone.

A discontinued product is a more mundane but very real reason too, sometimes the decision is made for you, and the question becomes how to switch smoothly rather than whether to switch at all.

Reasons that sound better than they are

Wanting variety for its own sake, or switching because a food is marketed with a trend you've seen elsewhere, aren't necessarily bad ideas, but they're not the same as a dog needing a change. Most dogs don't get bored of the same food the way people imagine, and a dog eating well, maintaining a healthy weight, and showing no digestive issues doesn't usually benefit from being switched purely for variety.

A higher price tag also isn't automatically a sign of a better food for your particular dog, a well-formulated complete diet at a moderate price can suit a dog just as well as a premium one, and the ingredients list and how your dog actually does on it matter more than the price on the bag.

How to switch, once you've decided

Whatever the reason, switch gradually over seven to ten days, mixing increasing amounts of the new food with decreasing amounts of the old, rather than changing the bowl over in one go. A sudden switch is one of the most common causes of a temporary digestive upset, which can then look like the new food doesn't agree with your dog when it's really just the speed of the change.

Keep an eye on stools, appetite and energy over the following couple of weeks, and speak to your vet if anything seems off, rather than switching again straight away, it can take a little time to properly judge whether a new food suits your dog.

Common questions

How often should I change my dog's food?: There's no fixed schedule, most dogs do well staying on a suitable food for a long stretch, and changes are best made for a specific reason, such as a life stage change or a health concern, rather than on a routine.
Can changing food upset my dog's stomach?: Yes, particularly if it's done suddenly. A gradual switch over about a week to ten days, mixing the new food in gradually, is far less likely to cause loose stools or an upset stomach than swapping the bowl over all at once.
Is a more expensive dog food always better?: Not necessarily. Price doesn't directly correlate with how well a food suits your individual dog, a moderately priced complete diet that your dog does well on is a perfectly good choice, and the ingredients and your dog's response matter more than the price.
When should I speak to my vet before changing food?: If your dog has a diagnosed health condition, ongoing digestive issues, or unexplained weight change, it's worth discussing a food change with your vet first rather than switching on your own, since the right diet may depend on what's actually going on.

Sources

Written against guidance published by UK veterinary and welfare organisations. Always confirm specifics with your own vet.

Written by Matt Garnett, who runs Giddy Pets and is a lifelong pet owner — not a vet. This is general information, not veterinary advice, and it cannot replace an examination by the vet who knows your animal. How we write these guides.