Subway has joined Chipotle, Panera, Chick-fil-A and McDonalds on a growing list of fast-food restaurants that have pledged to begin selling meat from suppliers that raise animals without using antibiotics. According to a report from NPR, the sandwich shop announced on Tuesday that it would set a timetable for its beef, chicken and pork suppliers to stop using antibiotics.

This poses a significant challenge for Subway. McDonalds and Chick-fil-A have only pledged to sell antibiotic-free chickens, and beef and pork are a much more difficult promise to keep. According to the company’s statement, it will take ten years to rid the beef and pork supply of antibiotics completely.

The movement against antibiotics has precipitated serious changes in the poultry industry, with companies like Tyson and Pilgrim’s Pride onboard with ditching the antibiotics that are also used to treat human infection. The main fear with eating meat treated with antibiotics is the development of super-drug-resistant bacteria that could break out and cause widespread infection.

Perdue Farms has led the change in the poultry industry, with 95 percent of its chickens off of human antibiotics and roughly half receiving none whatsoever.

Cattle and pigs are much bigger animals, and are more susceptible to disease. Producers still need to rely on antibiotics to some degree, and have only begun to consider the changes requested by food consumers.