How does the nutrient content of cow’s milk differ from human milk?

The nutrient composition of cow’s milk differs significantly from human milk, as each is biologically tailored to the specific growth requirements of its own species.12

Key Nutritional Differences

When comparing mature human milk to cow’s milk (per 100 grams), the following variations are notable:

• Protein: Cow’s milk contains a much higher concentration of protein (approximately 3.29 g) compared to human milk (1.03 g). Specifically, cow’s milk is much higher in casein, which forms a dense, hard curd that is difficult for human infants to digest.21
• Minerals: Cow’s milk is significantly richer in minerals, particularly calcium (119 mg vs. 32 mg) and phosphorus (93 mg vs. 14 mg), which support the rapid skeletal development required by calves.2
• Carbohydrates: Human milk contains a higher level of lactose (6.89 g) compared to cow’s milk (4.66 g).2

Nutritional Considerations for Infants

Human breast milk is considered the superior food for infants, providing essential antibodies and immunologic factors that protect the gastrointestinal tract and reduce infection rates. Unmodified cow’s milk is not an ideal substitute for infants, as its high protein content can cause digestive issues and potential allergic reactions. When used in infant formulas, cow’s milk must be modified—often through dilution or heat treatment—to better approximate the nutritional profile of human milk.13