Are small dogs truly high-energy? New evidence reveals they might be—at least in terms of metabolism. This recent study investigates caloric needs in dogs of varying sizes and finds surprising differences that challenge existing feeding guidelines.
The domestic dog’s vast size variation has long intrigued veterinarians and animal scientists, but questions remain about how size influences metabolism and nutrition. In a 2023 study published in the Journal of Animal Science, researchers Allison P. McGrath, Lauren B. Hancock, and Emily M. Morris conducted a longitudinal investigation into the caloric needs of dogs across size categories—and found that small dogs consistently require more calories relative to their metabolic body weight (MBW).
Researchers analyzed daily caloric intake, MBW-adjusted caloric intake (kcal/kg0.75/day), and body weight in adult dogs classified as small (≤11 kg), medium (11–22 kg), and large (≥22 kg). The team also compared caloric needs between young and older small dogs. Despite adjusting for MBW, small dogs had significantly higher calorie requirements than medium and large dogs (P < 0.001), and this held true across age groups.
The study also found greater variance in caloric intake among small dogs, suggesting metabolic diversity within the group. Additionally, small dogs exhibited a higher average activity factor (1.7 vs. 1.5 for medium and large breeds), underscoring their elevated energy demand even at rest or moderate activity levels.
These findings challenge the adequacy of current one-size-fits-all nutritional guidelines, especially for small breeds. The authors suggest that updated, size-specific feeding recommendations may better support healthy weight maintenance and long-term health in small dogs.
