The Feline Metabolism
Cats are obligate carnivores, meaning their bodies are evolutionarily tuned to process protein and fat rather than carbohydrates. Unlike dogs, cats have a unique metabolic pathway that requires specific amino acids like Taurine and Arginine found only in animal tissues.
Indoor vs. Outdoor Caloric Needs
Environment is the single biggest factor in feline obesity. An indoor, neutered cat has an energy requirement roughly 30% lower than a cat that spends time hunting or roaming outdoors.
- Indoor Neutered (1.2x RER): The default setting for most house cats to prevent weight gain.
- Active/Outdoor (1.4x - 1.6x RER): For cats that spend significant daily energy on physical activity.
- Nursing/Lactating (3.0x RER): Extreme energy needs during milk production.
"Mochi" is a 6-month-old kitten weighing 7 lbs.
- Kitten Phase: Mochi currently eats ~400 kcal/day (2.5x RER) to support
growth.
- The Transition: At 12 months, if Mochi is neutered and stays indoors, her
needs will drop to ~200 kcal/day.
- The Risk: Continuing kitten portions into adulthood is the #1 cause of
early-onset feline diabetes.
Strategic Feeding FAQ
Vets use a 1-9 scale. You should be able to feel your cat's ribs easily but not see them. If you cannot feel the ribs, your cat is likely in the "sedentary/obese prone" category.
High-protein diets help cats maintain lean muscle mass while burning fat. Low-protein, high-carb "diet" foods can often lead to muscle wasting in felines.