All formulas
Head to head
Bubs Stage 1 Organic Grass Fed vs Kirkland Signature ProCare
In independent testing, Kirkland Signature ProCare showed lower heavy-metal levels overall (purity 86 vs 77). The full lab numbers, metal by metal:
| Purity score | 77B | 86A |
| Lead ppb | 1.9 | 1.7 |
| Total Arsenic ppb | 2.9 | — |
| Cadmium ppb | 1.9 | — |
| Aluminum ppb | 1,985 | 1,143 |
| Price | $1.70/oz | $0.48/oz |
| Est. cost at 28 oz/day | $7.40/day | $2.07/day |
| Origin | AU / NZ | US |
| Base | Cow's milk | Cow's milk |
| Buy | Buy |
BubsStage 1 Organic Grass Fed
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.