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Enfamil Enspire Optimum vs Kirkland Signature ProCare
In independent testing, Enfamil Enspire Optimum showed lower heavy-metal levels overall (purity 100 vs 86). The full lab numbers, metal by metal:
| Purity score | 100A | 86A |
| Lead ppb | — | 1.7 |
| Aluminum ppb | 50 | 1,143 |
| Price | $1.85/oz | $0.48/oz |
| Est. cost at 28 oz/day | $8.05/day | $2.07/day |
| Origin | US | US |
| Base | Cow's milk | Cow's milk |
| Buy | Buy |
EnfamilEnspire Optimum
Kirkland SignatureProCare
Lab data: Consumer Reports independent testing, March 2025. Purity scores are relative to the tested cohort — methodology. Not medical advice; consult your pediatrician.