Ever noticed this tiny phrase printed on your milk gallon's label: "this milk does not come from cows treated with rBGH"? Maybe, maybe not. But what does it mean? Should you care?

Approved by the FDA in 1993, rBGH, or recombinant bovine growth hormone, is a protein hormone often injected into cows to increase milk production. The hormone is manufactured by Monsanto under the name Posilac. While approved and widely used in the U.S., Posilac is illegal in Europe and Canada due to the potential harmful effects on cattle and the public.

According to the Center for Food Safety, in cows treated with rBGH, significant health problems often develop, including a 50% increase in the risk of lameness (leg and hoof problems), over a 25% increase in the frequency of mastitis (udder infections), and serious animal reproductive problems, like infertility, cystic ovaries, fetal loss and birth defects.

Furthermore, the NRDC's Simple Steps reports that "cows 'burn out' from excess milk production and with shorter lives and more disease, dairy cows get more antibiotics." The residues of these antibiotics may end up in our milk and dairy products.

Despite loud public pleas to reverse rBGH's approval, the FDA maintains that there are no opposing arguments that "demonstrate any human food safety issue related to the use of Posilac” and therefore they haven't conducted and long-term studies.

Next time you reach for the milk, you may want to take a closer look at that label. Or play it safe and buy organic.

Images obtained from Flickr (Noel Cornell, Ilja, Brittney Bush)