Human-milk substitutes existed before the modern age of formulas. Because some infants could not be fed by their mothers, humans adopted two methods for substitute feedings. The most obvious was the utilization of a surrogate mother or wet nurse, who would feed the child human milk. The alternative, being the second option, was to feed the child milk obtained from another mammal.
The most frequently used sources were the cow, sheep and goat. Until the end of the nineteenth century, the use of a wet nurse was by far the safest way to feed infants who could not be breastfed by their mothers. As general sanitation measures improved during the latter part of the nineteenth century, and as differences in composition between human milk and that of other mammals were defined, feeding animal milk became more successful.
However few infants survived until infant formulas based on cow milk with added water and carbohydrate were introduced. In the year 1915 a formula called “synthetic milk adapted” was developed with nonfat cow milk, lactose, oleo oils and vegetable oils. This was the basis for modern commercially prepared formulas.