Microbiome: The Link Between Gut Health and Your Dog’s Mood

We’ve all seen it—that pup who suddenly won’t settle, whines at the window, or seems uncharacteristically anxious. Maybe they’re just having “one of those days.” But what if their behavior is rooted deeper… say, in their gut?

Your dog’s microbiome—the community of trillions of bacteria, fungi, and other microbes living in their digestive system—plays a bigger role in mood than most pet parents realize. It’s not just about digestion; it’s about emotion, stress resilience, and even playfulness.

Here are three powerful ways your dog’s gut could be influencing their behavior.

1. The Gut-Brain Highway: Not Just a One-Way Street

There’s a direct line of communication between your dog’s gut and brain called the gut-brain axis. When the gut microbiome is out of balance—whether due to diet, antibiotics, illness, or stress—it can send distress signals to the brain.

Signs this might be happening:

• Sudden behavior changes like irritability or restlessness
• Decreased interest in play or social interaction
• Hyperactivity or unusual clinginess

Gut imbalance doesn’t always cause digestive symptoms. Sometimes, it simply looks like a mood shift.

🦴 Pro tip: A microbiome-friendly diet like Mills Daily Packs, made with all-natural ingredients and tailored to your dog’s needs can help maintain a healthy gut ecosystem and support calmer behavior.

2. Serotonin: The Mood Molecule Made in the Gut

Over 90% of your dog’s serotonin, the chemical that regulates mood, is produced in the gut, not the brain. If you dog’s gut health is off, serotonin production may be too, making it harder for your dog to stay calm and happy.

Possible red flags:

• Pacing or panting without obvious cause
• Sensitivity to noise or routine changes
• Signs of low mood or withdrawal

While you can’t "see" serotonin levels, your dog’s overall demeanor is a good barometer.

🐾 Pro tip: Include prebiotics (like pumpkin or oats) and probiotics in your dog’s meals (which also exists in Mill Daily Packs). These support beneficial bacteria that help produce serotonin naturally.

3. Stress and the Microbiome: A Two-Way Tug-of-War

Stress can disrupt your dog’s microbiome—and a disrupted microbiome can make your dog more sensitive to stress. It’s a loop, and sometimes, a stuck one.

Stressors could be:

• Travel, boarding, or loud environments
• A new pet, baby, or significant household change
• Diet change or irregular feeding schedules

Signs to look for:

• Skipping meals (even favorite treats)
• Loose stools or inconsistent poop
• Heightened alertness or “jumpy” behavior

📦 Pro tip: Consistency is your best friend. Try calming pre-meal rituals, daily routines, and gut-soothing foods.

Packing it All Up

Your dog’s moods aren’t just about what’s going on in their head—they’re deeply connected to what’s happening in their belly. If your pup is showing signs of anxiety, unpredictability, or mood changes, it might be time to look inward…to the gut.

Want to give your dog’s microbiome a daily boost? Try MillsDailyPacks—made with gut-nourishing ingredients.