The short answer: Hill’s Science Diet (C/61) edges Hill’s Prescription Diet Metabolic (C/58) by 3 points. The prescription weight-loss formula actually scores lower than the standard retail food — Metabolic trades ingredient quality for calorie control, adding powdered cellulose and soybean meal while dropping fresh chicken entirely. If your dog needs to lose weight, Metabolic serves that medical purpose despite the lower score. If not, Science Diet is the better food on ingredients alone.

The scores

Hill’s Science Diet: C (61/100)

Hill’s Prescription Diet Metabolic: C (58/100)

Both are solidly in C-grade territory. The 3-point gap is narrow, but it goes in the unexpected direction — the cheaper, non-prescription food wins on ingredient quality.

How the ingredients compare

Science Diet: Chicken, Cracked Pearled Barley, Brown Rice, Brewers Rice, Whole Grain Wheat

Metabolic: Whole Grain Wheat, Whole Grain Corn, Chicken Meal, Powdered Cellulose, Soybean Meal

The difference is stark. Science Diet leads with chicken — actual whole chicken. Metabolic leads with two grains, then chicken meal (a rendered product), then wood pulp fiber, then soybean meal. Metabolic’s entire top-five design prioritizes satiety and calorie control over protein quality.

Where Hill’s Science Diet pulls ahead

Chicken as the first ingredient gives Science Diet a meaningful protein advantage. It also includes cracked pearled barley and brown rice — higher-quality grains than the whole grain wheat and corn that lead Metabolic. Science Diet avoids powdered cellulose and soybean meal entirely. It also includes FOS prebiotics, which Metabolic lacks. The ingredient list, while still grain-heavy, is simply cleaner. Shop on Amazon →

Where Hill’s Prescription Diet Metabolic holds its own

Metabolic isn’t trying to be a better Science Diet — it’s trying to help overweight dogs lose weight safely. Powdered cellulose creates satiety without adding calories. Lipoic acid supports glucose metabolism. L-Carnitine assists fat burning. Coconut oil provides medium-chain triglycerides for energy. These are functional weight-loss ingredients that Science Diet doesn’t need or include. The lower ingredient quality score is a deliberate trade-off for therapeutic efficacy. Shop on Amazon →

The bottom line

Hill’s Science Diet (C/61) beats Metabolic (C/58) on ingredient quality by 3 points. But this comparison misses the point: Metabolic exists to solve canine obesity, a condition that shortens lifespan more than any ingredient quality difference. If your vet prescribed Metabolic, use it for weight loss. Once your dog reaches target weight, transition to Science Diet or a higher-quality option like Blue Buffalo (B/78).