The osmolality of standard infant formulas at a caloric density of 20 kcal/oz generally falls within which range?

• A. 100-200 mOsm/kg
• B. 400-600 mOsm/kg
• C. 200-380 mOsm/kg
• D. 500-700 mOsm/kg

Answer: (C)

Osmolality is the concentration of osmotically active particles per kilogram of water, so it rises with the number of dissolved nutrients and minerals in the formula. For standard term infant formulas at a caloric density of 20 kcal/oz, manufacturers balance carbohydrate, protein, and minerals to stay moderate, avoiding very high osmotic loads. This typically places osmolality around a few hundred mOsm/kg, commonly in the 250–350 range, which fits within the 200–380 mOsm/kg window. Values higher than this (toward 400–700) belong to more concentrated or specialized formulas and are generally not characteristic of standard 20 kcal/oz formulas. Hence, the standard-density formulas generally fall in the 200–380 mOsm/kg range.