“Right now, 80 percent of all of the antibiotics sold in the US are sold to livestock producers. When livestock producers use those drugs routinely, some bacteria become resistant,” explained Jonathan Kaplan, the food and agriculture program director at the Natural Resources Defense Council.
If those bacteria spread to people, and people become ill, antibiotics won't be able to treat them, Kaplan said. But by ditching the use of human-medicine antibiotics, producers can help prevent the development of these resistant bacteria in the first place.
McDonald's chickens will still be raised with antibiotics, just not the ones used in human medicine.
"Those chickens will still get ionophores, which technically are antibiotics but we're not too worried about that because ionophores are not used in human medicine and there's not a lot of evidence that their use creates resistance risk to human antibiotics," Kaplan said.
Antibiotics use in livestock production has surged over the past few decades, from virtually nonexistent in the 1960s to standard practice today. It started when farmers discovered that routine use of antibiotics made the animals grow more quickly, Kaplan said. Then as farms transformed into more factory-like environments, animals were also living in closer quarters with one another, which made diseases spread more quickly. Using antibiotics routinely, and as a preventative measure before the animals got sick, just made good business sense. But we're now starting to see the many negative effects of quickly growing cheaper meat.
In recent years, pressure from the public and other restaurant chains like Chipotle and Panera Bread have incentivized chicken producers to stop using human medicine antibiotics on their birds. Just last year, Perdue—one of the largest chicken producers in the country—ditched human antibiotics for their animals unless prescribed by a veterinarian.
But the NRDC and other proponents of eliminating human antibiotics in farming aren't satisfied yet. For one, Kaplan said, McDonald's pork and beef are still raised with human medicine antibiotics and that industry has been slower to adopt the changes, so it won't be as easy for McDonald's to source antibiotic-free meat.
"Larger animals live longer, they have a longer life cycles, whereas in chicken production you're starting with a brand new flock every 35 days or so. And there are fewer non-human antibiotics for pork and beef producers," Kaplan said.
He also noted that McDonald's international restaurants aren't making any switches and the fast food giant recently released a global vision statement where it outlined sourcing animals who are raised with antibiotics "for disease prevention." This leaves the door open for any kind of antibiotic use, since technically they are preventing disease in the animals.
The chicken swap in the US is a step, but Kaplan says we still have a long way to go.