Does milk contain hormones?

In Ireland and the European Union, there is a total ban on the use of hormones for milk stimulation or growth promotion in farm animals, including dairy cows. They are banned under EU Directive 81/602/EEC. Use of such substances is a criminal offence with strict legal penalties. The Department of Agriculture, Food and the Marine is the designated competent authority for the enforcement of milk quality and safety legislation, with farm inspections conducted routinely.

The concentration of naturally occurring hormones in milk is negligible and, for the most part, are destroyed by proteolysis during digestion. To put this into biological perspective, it is estimated that the typical intake of the hormone, IGF-1 from a standard glass of milk is insignificant at approximately 0.03 % of the body’s own natural daily production.

Extra Information:

Some substances with a hormonal action are approved for therapeutic use in Ireland. These reproductive medicines require a veterinary prescription, and documentation must be available to show they were used under veterinary supervision. They are not used for the purpose of milk production, and are typically targeted at a small proportion of cows that have been diagnosed with reproductive problems that require therapy (ovarian cysts, anoestrous, uterine infection). Although uncommon in Ireland, hormonal treatment can be used for the synchronisation of breeding in maiden (non-milking) heifers. Routine induction of calving is prohibited under the Sustainable Dairy Assurance Standard.