NOW that Congress has pushed through its complicated legislation to reform the health insurance system, it could take one more simple step to protect the health of all Americans. This one wouldn’t raise any taxes or make any further changes to our health insurance system, so it could be quickly passed by Congress with an outpouring of bipartisan support. Or could it?

More than 30 years ago, when I was commissioner of the United States Food and Drug Administration, we proposed eliminating the use of penicillin and two other antibiotics to promote growth in animals raised for food. When agribusiness interests persuaded Congress not to approve that regulation, we saw firsthand how strong politics can trump wise policy and good science.

Even back then, this nontherapeutic use of antibiotics was being linked to the evolution of antibiotic resistance in bacteria that infect humans. To the leading microbiologists on the F.D.A.’s advisory committee, it was clearly a very bad idea to fatten animals with the same antibiotics used to treat people. But the American Meat Institute and its lobbyists in Washington blocked the F.D.A. proposal.

In 2005, one class of antibiotics, fluoroquinolones, was banned in the production of poultry in the United States. But the total number of antibiotics used in agriculture is continuing to grow. According to the Union of Concerned Scientists, 70 percent of this use is in animals that are healthy but are vulnerable to transmissible diseases because they live in crowded and unsanitary conditions.

In testimony to Congress last summer, Joshua Sharfstein, the principal deputy commissioner of the F.D.A., estimated that 90,000 Americans die each year from bacterial infections they acquire in hospitals. About 70 percent of those infections are caused by bacteria that are resistant to at least one powerful antibiotic.