Changing your dog’s food might seem straightforward, but for their digestive system, a sudden switch can sometimes be a lot to deal with.

Whether you're moving to a different brand, changing protein sources, switching from kibble to raw food or introducing a new diet because your dog's needs have changed, gradually transitioning your dog’s food can help make the process much gentler on their stomach.

In this guide, we explain how to change your dog’s food gradually, what to watch for during the transition and how supporting their gut with Proflax Digestive Support can help maintain healthy digestion along the way.

Why Should You Change Your Dog’s Food Gradually?

Your dog's digestive system becomes accustomed to the food they regularly eat.

The gut is home to billions of microorganisms, collectively known as the gut microbiome. This delicate ecosystem plays an important role in digestion, nutrient absorption and overall wellbeing.

When you suddenly introduce a completely different food, the balance of proteins, fats, fibres and other nutrients reaching the digestive system can change overnight.

For some dogs, changing food too quickly may lead to temporary digestive upset, including:

• Loose stools or diarrhoea
• Excess wind
• Tummy gurgling
• Bloating
• Changes in stool frequency
• Reduced appetite
• Occasional vomiting
• General digestive discomfort

A slower transition gives your dog's digestive system and gut bacteria more time to adapt to the new food.

How Long Does It Take to Change a Dog’s Food?

For most dogs, gradually changing food over around 7–10 days is a sensible approach.

Dogs with particularly sensitive stomachs may benefit from an even slower transition.

Days 1–3

75% old food + 25% new food

Introduce a small amount of the new food alongside your dog's usual diet.

Days 4–6

50% old food + 50% new food

If your dog's stools and digestion remain normal, increase the proportion of new food.

Days 7–9

25% old food + 75% new food

Your dog is now eating mostly their new diet.

Day 10 onwards

100% new food

If your dog is comfortable and their stools remain healthy, you can move completely onto their new food.

There is no need to rush. If your dog develops loose stools or digestive discomfort, stay at the current stage for a little longer before increasing the amount of new food again.

Can Changing Dog Food Cause Diarrhoea?

Yes. Loose stools are one of the most common problems owners notice after changing dog food, particularly if the switch happens suddenly.

That does not always mean the new food is unsuitable.

Sometimes your dog's digestive system simply needs more time to adjust.

A change in protein source, fat content, fibre level or ingredients can temporarily affect digestion and the balance of bacteria within the gut.

This is one of the main reasons why a gradual dog food transition is usually preferable to an overnight change.

Supporting Your Dog’s Gut During a Food Change

A healthy digestive system is not simply about what goes into your dog's bowl.

The health and balance of the gut microbiome can influence how efficiently food is digested and nutrients are absorbed.

This is where targeted digestive support can be particularly useful.

Proflax Digestive Support is a 100% natural pre- and probiotic powder designed to support healthy digestion and a balanced gut microbiome. It is formulated to help support nutrient absorption, healthy stools and sensitive stomachs.

It can therefore be particularly useful during periods of dietary change, when your dog's digestive system may need a little extra support.

Why Use Digestive Support When Changing Dog Food?

Changing diet introduces new ingredients for your dog's digestive system to process.

Supporting the gut at the same time can help make the transition gentler.

Proflax Digestive Support contains a combination of natural herbs, prebiotics and probiotics selected to support digestive health.

The formula helps to:

• Support a balanced gut microbiome
• Maintain smooth, healthy digestion
• Support nutrient absorption
• Help maintain healthy stools
• Soothe sensitive stomachs
• Support dogs prone to gas and bloating
• Provide natural pre- and probiotic support

You can also explore the wider Proflax Digestive Support collection if your dog needs ongoing help with gut health, digestion or digestive sensitivity.

Prebiotics vs Probiotics: What’s the Difference?

You may see both terms mentioned when looking at supplements for your dog's gut.

Probiotics

Probiotics are beneficial live microorganisms that help support a healthy balance of bacteria within the digestive system.

Proflax Digestive Support contains two probiotic strains: Enterococcus faecium and Bacillus subtilis. These are included to support digestion, nutrient absorption and gut health.

Prebiotics

Prebiotics are different.

Rather than supplying beneficial bacteria directly, prebiotics help nourish the good bacteria already living within the gut.

Proflax Digestive Support contains natural prebiotic ingredients including chicory root extract and dandelion root.

Using prebiotics and probiotics together helps support the wider gut microbiome rather than concentrating on digestion alone.

What’s in Proflax Digestive Support?

The formula combines digestive herbs, prebiotics, probiotics and natural clays.

Chicory Root

A natural prebiotic that helps promote healthy gut bacteria.

Dandelion Root

Rich in prebiotic fibre and included to support normal digestion.

Slippery Elm

Included to help soothe the gut lining and support healthy stool consistency.

Chamomile

A gentle herb used to support calm, comfortable digestion.

Fennel

Included to support digestion and help with tummy gurgles.

Probiotics

The formula contains Enterococcus faecium and Bacillus subtilis, providing targeted probiotic support for the gut microbiome.

Together, these ingredients provide broader digestive support during periods when your dog's gut may be adapting to change.

Can You Use Digestive Support Before Changing Your Dog’s Food?

Introducing digestive support before you begin changing food can be a useful way of supporting the gut ahead of the transition.

You could begin adding Proflax Digestive Support to your dog's normal food first, then gradually introduce their new food once the supplement has become part of their routine.

Continue using it throughout the transition and afterwards if your dog benefits from ongoing digestive support.

This may be particularly useful for dogs that:

• Have sensitive stomachs
• Regularly experience loose stools
• Are prone to wind or bloating
• Have previously struggled when changing food
• Are moving onto a very different type of diet
• Need ongoing digestive and gut support

Changing From Kibble to Raw Dog Food

Moving from kibble to raw feeding can be a particularly significant dietary change.

The ingredients, moisture content, protein levels and overall composition of the diet can all be very different.

Some dogs adapt quickly, while others need more time.

If you're moving your dog onto raw food, keep an eye on:

• Stool consistency
• Appetite
• Energy levels
• Wind and bloating
• Frequency of bowel movements

Don't be alarmed if stools look slightly different on a new diet. Changes in food composition can naturally alter the colour, volume and consistency of your dog's poo.

The important thing is to monitor your dog and make changes gradually.

Changing Protein Sources

Sometimes the type of food stays broadly the same but the protein changes — for example, from chicken to lamb, beef, turkey or fish.

This can still affect digestion.

Dogs with sensitive stomachs may benefit from introducing a new protein gradually rather than replacing their existing food immediately.

Introducing one change at a time can also make it much easier to identify which ingredients suit your dog best.

Avoid Changing Too Many Things at Once

When introducing a new food, it can be tempting to change treats, supplements and meal routines at the same time.

Keeping everything else relatively consistent makes it much easier to understand how your dog is responding to their new diet.

If their stools suddenly change, you'll have a better idea of what may have caused it.

Keep Treats Simple During the Transition

Treats count too.

If your dog is adapting to a new diet but is also eating lots of different chews, table scraps and treats, their digestive system is dealing with several variables at once.

During the first week or two of a food transition, keeping treats simple can make the change much easier to monitor.

Watch Your Dog’s Poo

Your dog's poo is one of the easiest ways to monitor how well they are adapting to their new food.

Ideally, stools should be:

• Firm but not hard
• Easy to pick up
• Consistent in shape
• Passed without excessive straining
• Relatively consistent from day to day

One softer stool is not necessarily a reason to abandon a new food.

Instead, consider slowing the transition and giving your dog's digestive system more time to adjust.

Persistent diarrhoea, repeated vomiting, blood in the stool, significant discomfort or a dog that appears unwell should always be discussed with your vet.

What If My Dog Has a Sensitive Stomach?

There is no single food that suits every dog.

If your dog has a particularly sensitive digestive system, consider transitioning more gradually — perhaps over 10–14 days or longer.

Keep their diet relatively simple during this period and monitor stools carefully.

Supporting the gut microbiome with prebiotics and probiotics may also be particularly useful for dogs that are naturally prone to digestive sensitivity.

You can explore more options for supporting digestion in the Proflax Gut Health & Digestive Support collection.

How Do You Know if a New Dog Food Is Working?

Don't judge a new diet after one meal.

Give your dog time to adjust and look at the wider picture over the following weeks.

Consider:

• Stool quality
• Appetite
• Digestion
• Wind and bloating
• Skin and coat condition
• Energy levels
• General wellbeing

Food is only one part of your dog's overall health, but consistent digestion and healthy stools are useful signs that their digestive system is coping well with their new diet.

Changing Your Dog’s Food Doesn't Need to Be Complicated

The biggest rule is simple: go slowly.

Gradually introduce the new food, watch your dog's digestion and allow their gut time to adapt.

For dogs with sensitive stomachs — or whenever you're making a significant change to their diet — Proflax Digestive Support provides natural prebiotic, probiotic and herbal support for healthy digestion.

And if you're looking for broader support, browse the full Digestive Support collection.

Old food → gradually introduce new food → support the gut → monitor your dog.

Simple.