Rock Doc: What antibiotics might be doing to us

By E. Kirsten Peters, College of Agricultural, Human & Natural Resource Sciences

peters-e-k-2010-80PULLMAN, Wash. – It’s astonishing to think about, but when my grandfather was born one in five children didn’t live to see their fifth birthday, in large part due to endemic and epidemic diseases. Today that’s all changed.

But although doctors can do a great deal to help the ill, it’s also true that chronic diseases plague us. And a number of these maladies seem to be on the rise. Diabetes, asthma, celiac disease and food allergies are all increasing in frequency. Most obvious of all, obesity is becoming more and more common.

Useful microorganisms affected

Dr. Martin Blaser of New York University thinks he understands at least part of what’s going on: medical treatments themselves are contributing to the rise of some chronic health problems. His new book, “Missing Microbes: How the overuse of antibiotics is fueling our modern plagues,” explores the link between changes in our internal microbes and the list of chronic diseases so many of us contend with.

Antibiotics are a blessing. But if Blaser is right, they are also a curse. Both things can be true. To take just one malady, let’s focus on obesity.

Our bodies host many trillions of microorganisms, and important changes in those populations occur when we take antibiotics. Blaser’s book outlines the ways in which a number of microorganisms, including ones that are useful to you, are affected when you take antibiotics.

Most antibiotics don’t end up in pills we get from pharmacies. Instead, most of the drugs go into the cattle, swine and poultry that we eat.

Fattening us up?

The reason so much antibiotic is given to livestock is that the animals gain more weight when they are given antibiotics in their feed. It pays for farmers to buy antibiotics and give them to whole herds.

Blaser’s book asks whether antibiotics given to people could have a similar effect as in livestock. Antibiotics, especially those given to kids, may be leading both to more growth and to putting on more fat, including in later life.

The book reviews experiments with mice in Blaser’s lab that address this connection, as well as studies in human populations. The author concludes we may be inadvertently fattening up our young in our rush to use antibiotics to treat every sore throat or cough.

Educating doctors, patients

As Blaser sees it, antibiotics contribute to obesity and a host of other chronic diseases that have been on the rise.

He argues that our attitudes need to change. Doctors should be trained to think twice before prescribing antibiotics. The drugs should be reserved for truly serious conditions that aren’t going away on their own.

“Doctors and patients alike have never fully taken into account all the costs of using antibiotics. Once they do, I predict their use, especially in early childhood, will greatly diminish,” Blaser wrote in an email to me.

The progress we’ve made combating many bacterial diseases is stupendous. But it’s time we looked at what the overuse of antibiotics may be costing us.


Dr. E. Kirsten Peters, a native of the rural Northwest, was trained as a geologist at Princeton and Harvard. This column is a service of the College of Agricultural, Human and Natural Resource Sciences at Washington State University.