Should You Add Water to Your Dog’s Kibble? Here’s What the Science Says

Adding water to dry kibble might seem like a simple decision, but it’s a topic that sparks a lot of debate among dog guardians and professionals alike. Some swear by it for better hydration and digestion, while others caution against potential risks like bloat, bacterial growth, or diminished dental benefits. So who’s right?

To answer that, let’s break down what the science actually tells us, examine common myths, and explore whether there might be better options than simply soaking dry food.

 

 

***

The Believed Benefits of Soaking Kibble

It’s a common belief that adding water to kibble helps with digestion, chewing (especially for puppies or seniors), hydration, satiety and weight control. But how much of this is based on research and how much is anecdotal?

A 2021 study titled “Effects of Softening Dry Food with Water on Stress Response, Intestinal Microbiome, and Metabolic Profile in Beagle Dogs” examined 20 young beagles. Half were fed standard dry food (DF), and the other half received the same food softened with water (SDF) over a 21-day period.

Key findings: no significant differences in body weight or nutrient digestibility. Dogs fed the softened kibble had higher cortisol levels, suggesting greater stress. There was an increase in potentially harmful gut bacteria (e.g., Streptococcus, Enterococcus, Escherichia-Shigella). Levels of Faecalibacterium, a beneficial gut bacterium, decreased.

These findings challenge the belief that soaking improves digestion. In fact, the results hint at the opposite.

Important caveats: the study didn’t specify how long the soaked food sat out before feeding. The dogs were only 5 months old, and the study lasted 21 days. No analysis was done on stomach acidity or pH changes, which are crucial for digestion and microbial control.

 

***

What About Hydration?

Hydration is often cited as the top reason for soaking kibble. But not all water hydrates equally. Free water (e.g., from bowls or soaked kibble) is absorbed quickly but also excreted just as fast.

Intracellular water, which comes from food—especially raw meat—is absorbed slowly, alongside electrolytes and nutrients, and offers better support for cellular hydration. In the wild, dogs hydrate primarily through prey, not from drinking water.

Kibble, which is typically around 10% moisture, is far removed from the moisture-rich composition of natural diets (60–75%). Therefore, adding water to kibble can help somewhat, but it’s not a replacement for a moisture-rich, biologically appropriate diet.

 

***

Does It Help with Weight Loss?

A 2017 study titled “The effect of reducing energy density, via the addition of water to dry diet, on body weight and activity in dogs” looked at 46 Miniature Schnauzers over two 28-day periods.

All dogs were first fed hydrated food at maintenance levels (100% MER). Then dogs were overfed (200% MER), and split into two groups: one got dry kibble, the other got hydrated food (72% moisture).

Results: Dogs on the hydrated food gained weight faster (about 19g/day more on average). Activity levels declined in the dry food group, but remained stable in the hydrated group.

Conclusion: hydrating kibble is not a reliable tool for weight control unless portions are carefully managed.

 

***

Common Concerns: Bloat, Bacteria, and Teeth

When it comes to soaking dry dog food, many guardians express concerns around three potential issues: the risk of bloat, bacterial contamination, and loss of dental benefits from crunchy kibble. Let’s take a closer look at each of these concerns, separating myth from fact and examining what we currently know from science and experience.

1. Bloat (Gastric Dilatation-Volvulus)

Bloat, or more specifically Gastric Dilatation-Volvulus (GDV), is a serious and potentially fatal condition in dogs. It occurs when the stomach fills with gas, food, or fluid and then twists (volvulus), cutting off blood flow and trapping its contents. GDV is considered a medical emergency and can lead to shock and death if not treated quickly.

Which Dogs Are at Risk?

• Large and giant breeds with deep chests are the most susceptible. Breeds like Great Danes, Weimaraners, Irish Setters, and Standard Poodles.

• Dogs with a family history of bloat are also at higher risk.

• Dogs that eat rapidly, are anxious, or engage in strenuous activity before or after meals may also be more vulnerable.

Is Adding Water to Kibble a Cause?

There is currently no scientific evidence that soaking kibble with water directly causes or increases the risk of bloat. In fact, some theories suggest that softening kibble might reduce the time it spends expanding in the stomach, potentially reducing gas buildup.

However,other factors are more strongly associated with bloat:

• Eating too quickly

• Drinking a large amount of water immediately after eating

• Eating one large meal per day rather than two or more smaller meals

• Raised feeding bowls (controversial and debated)

• Stress or anxiety during mealtimes

If you’re concerned about bloat:

• Feed multiple smaller meals throughout the day

• Use a slow feeder bowl to reduce gulping

• Avoid vigorous exercise around mealtimes

• Ensure a calm environment during feeding

Adding water to food should not be ruled out solely on the fear of bloat. In fact, some owners of large breeds prefer soaking food to pre-expand it, especially when kibble tends to swell in the stomach.

2. Bacterial Contamination

This concern is more concrete—and very real if precautions aren’t taken.

When you add water to kibble and let it sit, especially at room temperature or warmer, it creates the perfect environment for bacteria, yeast, and mould to multiply. This is particularly problematic in warmer months or homes with high humidity.

How Long Is Too Long?

• Soaked kibble shouldnever sit out for more than 20–30 minutes.

• If your dog doesn’t finish the meal, refrigerate it immediately and discard it if uneaten after a few hours.

• Never reuse or “top up” old soaked kibble left in a bowl.

Some bacterial species, including Salmonella and Listeria, can proliferate quickly in moist, warm environments. And while many healthy dogs may not show symptoms of illness from mild exposure, dogs with weakened immune systems—puppies, seniors, or dogs recovering from illness—could become sick.

Also worth noting: even dry kibble, if left out in open air for extended periods, can attract pests and degrade in quality. This is why free feeding (leaving food out all day) is not recommended, especially with soaked kibble.

3. Dental Health: Does Crunchy Kibble Clean Teeth?

This is perhaps the most persistent myth in the pet food world—that dry kibble helps “clean” a dog’s teeth through mechanical abrasion.

Let’s be clear: standard kibble offers little to no dental benefit.

Why?

• Most dogs do not chew kibble thoroughly. They bite once or twice, then swallow.

• The particles left behind can stick to the teeth, promoting plaque buildup rather than removing it.

• The abrasive effect of kibble is minimal compared to the natural chewing dogs would do on raw meaty bones, which clean the teeth at the gumline.

Even so-called “dental” kibbles often rely on specific shapes or chemical additives (e.g., sodium hexametaphosphate) to help reduce tartar—but even these are not a substitute for proper dental care.

The Real Way to Maintain Oral Health:

• Brush your dog’s teeth daily or at least 3–4 times per week with a dog-safe toothpaste

• Provide appropriately sized raw meaty bones (only if safe and suitable for your dog)

• Use veterinary-approved dental chews as an occasional supplement—not a primary strategy

• Scheduleregular dental check-ups with your vet

Ultimately, relying on kibble for dental care is like us relying on crackers to clean our teeth—it’s wishful thinking, not a dental routine.

 

***

Better Alternatives to Water

 

1. Bone Broth: A Functional Hydration Booster

Bone broth isn’t just a culinary trend for humans—it’s a highly beneficial addition to your dog’s diet. When prepared correctly (without onion, garlic, or added salt), bone broth is rich in nutrients that support multiple systems in the body.

Why bone broth is a better choice than water:

• Supports digestion: Bone broth contains glycine, gelatin, and glutamine, which help maintain the gut lining and support healthy digestion.

• Balances pH: Unlike plain water, which can dilute stomach acid and slow digestion, bone broth helps maintain healthy gastric acidity, particularly important for breaking down proteins and killing harmful bacteria.

• Encourages eating: Its rich aroma and flavour can stimulate the appetite in picky eaters, recovering dogs, or seniors with diminished senses.

• Adds moisture and nutrition: Broth provides minerals like calcium, phosphorus, magnesium, and potassium—plus collagen, glucosamine, and chondroitin, which are beneficial for joint health.

You can use homemade or high-quality store-bought bone broth (ensure it’s free of additives, preservatives, or onions). It can be:

• Mixed with kibble to soften it

• Poured over meals as a topper

• Frozen into cubes and used as enrichment or treats

2.Goat’s Milk (Raw or Fermented)

Another excellent alternative is raw or fermented goat’s milk. It’s naturally rich in probiotics, enzymes, and medium-chain fatty acids, making it a gut-supportive hydration booster.

Benefits:

• Easy to digest, even for dogs with lactose sensitivity (due to its low lactose content and small fat globules)

• Containsanti-inflammatory andimmune-supportive compounds

• Promotes healthy microbiota and can be especially helpful for dogs with digestive upset or poor appetite

Like bone broth, goat’s milk can be served on its own, poured over meals, or used to soak dry food. Choose pasteurised or properly handled raw versions from reputable brands.

3. Herbal Infusions (Dog-Safe Teas)

Mild infusions of chamomile, ginger, or fennel tea can be used in small amounts to soothe the digestive tract or calm anxious dogs. These should be used occasionally and under guidance, especially in dogs on medication.

Herbal broths or teas can be especially helpful for:

• Dogs withupset stomachs

• Senior dogs with digestive sluggishness

• Post-operative care where appetite is reduced

Always ensure the herbs used are safe for dogs and offered in moderation. Watch our video for more information.

 

 

4. Moisture-Rich Whole Foods: The Ultimate Upgrade

Soaking kibble is often done to improve hydration—but it’s a bit like putting a plaster on a broken pipe. A much more effective approach is to incorporate real, fresh foods that naturally provide the moisture, nutrients, and bioavailable hydration your dog’s body evolved to thrive on.

Examples of moisture-rich whole foods:

• Lightly cooked meats (e.g. turkey, beef, chicken)

• Organs (e.g. liver, kidney, heart)

• Low-glycaemic vegetables (e.g. courgette, pumpkin, broccoli)

• Raw meaty bones (if your dog is a safe candidate)

• Whole eggs (cooked or raw with shell, depending on your feeding philosophy)

These foods typically contain 60–75% moisture, closely mimicking the water content found in prey animals. This not only keeps your dog better hydrated but also reduces the workload on the kidneys, improves nutrient absorption, and supports gut and skin health.

 

***

Final Thoughts

Adding water to kibble might seem like a harmless tweak, but it’s rarely the solution many hope it will be. While it can help soften food for dogs who need it, the science doesn’t support claims that it improves digestion, aids weight loss, or offers meaningful dental benefits. In some cases, it may even create new issues, from bacterial growth to elevated stress markers.

Instead of simply soaking kibble and hoping for the best, think bigger. Consider:

• Supporting hydration through whole, moisture-rich foods

• Choosing nutrient-dense liquids like bone broth or goat’s milk over plain water

• Prioritising gut health, real nutrition, and long-term wellbeing through a more natural, tailored diet

Your dog’s nutritional needs are as individual as they are. There’s no one-size-fits-all solution—but there are smarter, more supportive ways to meet them.