The present invention relates to a human milk fortifier as well as to several uses and a method for the production of such a fortifier. A particularly beneficial fortifier can be realised in that at least one human component based on a product directly or indirectly derived from human mammary secretion during non-pregnant, pregnant, lactating and/or involuting periods is used, giving rise to an optimally adapted fortifying effect which is particularly useful in the context of feeding preterm infants.