Numerous factors affect milk composition, and knowledge about their interactions is limited. The same can be said about the large number of studies comparing organic and conventional milk and the limited number of generally accepted research conclusions on the differences between organic and conventionally produced milk. This limitation arises for 2 reasons, the first of which is the lack of comparable conditions within and between trials. In general, most researchers have not controlled sufficient variables to allow a valid comparison between organic and conventionally produced cow milk. Diet composition and breed of cow are the minimum factors that need to be considered and reported when aiming to compare milk samples. The second reason is that current regulations for organic milk production do not allow for a distinct separation from conventionally produced milk. In other words, no “organic effect” exists that can be credited to a holistic combination of factors affected by the organic system. If animal genetics, health, breed, diet, management, or environment differs, then so will the composition of the milk produced.