The scores
Iams ProActive Health Smart Puppy: B (75/100) — Real chicken first, fish oil for DHA, brewers yeast and FOS for developing gut, dicalcium phosphate for bone growth. The strongest formula in the Iams lineup.
Purina Puppy Chow Complete: D (39/100) — Ground yellow corn leads, whole grain corn follows, meat and bone meal provides the primary animal protein. Minimal omega-3 supplementation. Budget ingredient profile.
How the ingredients compare
Iams Smart Puppy: Chicken, Ground Whole Grain Corn, Chicken By-Product Meal, Ground Whole Grain Sorghum, Dried Plain Beet Pulp
Purina Puppy Chow: Whole Grain Corn, Meat and Bone Meal, Corn Gluten Meal, Beef Fat, Soybean Meal
Iams leads with real chicken — a named, identifiable animal protein. Puppy Chow leads with corn. That single positioning difference explains most of the 36-point gap. In positions #2 through #5, Iams has one grain (corn) and one by-product meal; Puppy Chow has corn, corn gluten meal, beef fat, and soybean meal — three plant sources and one fat, with no whole meat at all. For a growing puppy whose amino acid demands are elevated, that composition matters.
Where Iams Puppy pulls ahead
Real chicken as the #1 ingredient: Named animal protein in the lead position delivers a complete amino acid profile a puppy's body can actually use. Meat and bone meal (Puppy Chow's primary protein) is AAFCO-legal but a lower-quality protein source with variable composition.
Fish oil for DHA: Iams Smart Puppy includes fish oil, the single most evidence-backed nutritional intervention for puppy brain and eye development. Puppy Chow has no comparable omega-3 source — a meaningful gap for any dog under 12 months old.
Growth-tuned mineral package: Iams uses dicalcium phosphate (delivers calcium + phosphorus in an orthopedic-friendly ratio), FOS prebiotic, and zinc for skin and coat. Puppy Chow's supplementation is thinner and less growth-specific. Shop on Amazon →
Where Puppy Chow holds its own
Price: Puppy Chow is meaningfully cheaper per pound. For owners on a strict budget, the difference matters. But the price-per-quality gap still favors Iams when you account for the ingredient profile.
Availability: Puppy Chow is in every grocery store and gas station. Iams is widely available but not quite as universal. For owners without reliable access to pet retailers, Puppy Chow's distribution is a real factor. Shop on Amazon →
The bottom line
If you have $5-10/month flexibility in your puppy food budget, Iams Smart Puppy is a substantially better choice than Purina Puppy Chow. The 36-point KibbleIQ gap is driven by real chicken vs corn-based protein, fish oil DHA for brain development vs no omega-3 source, and a growth-tuned mineral package vs basic supplementation. For the critical 12-month window of puppy development, those differences compound.