With major fast food chains like McDonald’s, Chick fil-A, Chipotle, and Panera all now sourcing at least some meat that wasn’t raised using medically important antibiotics, a coalition of some 50 consumer and health advocacy groups are asking Subway, the fast food chain with the most stores in the U.S., to give drug-free meat a try.

Overuse of antibiotics in livestock and by physicians has resulted in the development of bacteria that is now resistant to the drugs created to kill them. This can render those antibiotics useless, putting human life and safety at risk. Around three quarters of all antibiotics sold in the U.S. each year are for use in farm animals, much of it for non-medical uses.

According to the Centers for Disease Control and Prevention, more than 2 million Americans become infected with drug-resistant pathogens each year, with 23,000 dying annually as a result. A recent report from our colleagues at Consumers Union found that an overwhelming majority of U.S. physicians had recently treated patients antibiotic-resistant illnesses.

CU is one of the dozens of groups that signed the letter [PDF] to Subway CEO Frank De Luca, calling on him to agree to a phase-out schedule for ending the use of antibiotics in all the meat sourced by the chain.

Many farm animals are regularly treated — usually through their feed — with low doses of antibiotics, solely for the purpose of increasing the size of the animals. Scientists say this continual, sub-therapeutic use of these drugs only aids in the development of resistant pathogens.

“Antibiotics important for human medicine should only be used to treat sick animals and, on rare occasions, for non-routine disease control, but never for growth promotion, feed efficiency, or routine disease prevention,” reads the letter.

After decades of inaction, the FDA has in recent years slowly come around to the notion that it must do something to curb overuse of antibiotics. There are still too many loopholes that allow their continued overuse — like simply giving farmers the option of changing the reason they use drugs (from “growth-promotion” to “disease prevention”) without necessarily feeding their livestock any fewer drugs.

“While we will continue to push FDA to adopt stronger policies on antibiotics use in animal agriculture, companies like Subway can make a vital contribution to stemming antibiotic resistance by disallowing routine antibiotics use among your suppliers,” continues the letter. “Subway can also play a role in encouraging better animal husbandry on farms. Reduced crowding, improved diets, more hygienic conditions and longer weaning periods, among other changes, can minimize the need for prophylactic drugs.”

The groups acknowledge Subway’s current regional testing of a chicken sandwich in California with meat described as having been raised with “no antibiotics ever,” and expresses hope that this is the beginning of a new trend for the company.

“In the coming months, we hope you will move quickly to serve only meat and poultry produced without routine antibiotics in all Subway restaurants, and help protect the effectiveness of these essential medicines,” concludes the letter.

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