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Similac Soy Isomil vs Up&Up Soy
In independent testing, Up&Up Soy showed lower heavy-metal levels overall (purity 63 vs 55). The full lab numbers, metal by metal:
| Purity score | 55C | 63C |
| Lead ppb | 3.6 | 3.4 |
| Inorganic Arsenic ppb | — | 5.3 |
| Total Arsenic ppb | 4.7 | 6.7 |
| Cadmium ppb | 9.2 | 4.6 |
| Aluminum ppb | 89 | — |
| Price | $0.88/oz | $0.67/oz |
| Est. cost at 28 oz/day | $3.81/day | $2.90/day |
| Origin | US | US |
| Base | Soy | Soy |
| Buy | Buy |
SimilacSoy Isomil
Up&UpSoy
Lab data: Consumer Reports independent testing, March 2025. Purity scores are relative to the tested cohort — methodology. Not medical advice; consult your pediatrician.