Do Humans Get Fat From Antibiotics Given to Livestock?

Drugs that fight infection in the animals we eat help keep us healthy, but do they also make us fat like the livestock being beefed up before slaughter?

Researchers are now considering whether antibiotics can make humans gain weight, to the point that perhaps antibiotics in the meat we ingest can have a bloating effect on blubber.

Evidence is suggesting that the same antibodies that are used to fatten up livestock can lead to a fattening result in humans, too. Since the 1940s, scientists have been using antibiotics not only to keep animals healthy, but to increase what they call "feed efficiency." That's to say for every pound of feed given to animals, there's a higher weight-gain when dosed with antibiotics.

The question for America's large-scale farms is whether it's safe to pump up animals quartered in tight confines with antibiotics.

Mother Jones concludes that antibiotics spur changes in the "gut microbe," changing the way the stomach breaks down fat.

This is an integral part of the digestive tract in all animals, including humans. It's been linked to everything such as immune disorders such as asthma and allergies as well disease-fighting.

"Microbes in our gut are able to digest certain carbohydrates that we're not able to," an NYU researcher told Mother Jones. In a paper by a team of researchers at the university, it was shown that children who were exposed to antibiotics at an early age were 22 percent more likely to be overweight. Another study showed that mice exposed to small amounts of antibiotics over time "extracted more energy" from food than did mice in a control group.

According to the Animal Health Institute, antibiotics are a critical tool to prevent, control and treat disease in animals. In doing so, they also reduce the chance of bacterial transmission from animals to humans.

So the connection goes: do the antibiotics put into meat trickle down to our own guts? The answer seems to be yes. Though the FDA has limits on the amount of antibiotics put into animals, the small amounts we ingest are thought to build up over time.