‘Missing Microbes’: How Hard Should You Resist Antibiotics? And Why

(Photo: R. Zimmerman)

(Photo: R. Zimmerman)

The new book “Missing Microbes” posits that our rampant overuse of antibiotics is not just creating antibiotic-resistant “superbugs”; it is contributing to many of our modern maladies, particularly those affecting children: asthma, allergies, diabetes, obesity.

It’s an idea that has lately been gaining attention and adherents. But you’re especially likely to pay attention and be persuaded when you’re hearing about it from a leading authority on the microbial “ecologies” in our bodies that are damaged by antibiotics: Dr. Martin Blaser, director of the Human Microbiome Program at New York University. Dr. Blaser, who wrote “Missing Microbes,” is in town for a microbiology conference and will be on Radio Boston this afternoon. Our conversation, lightly edited:

As you write, antibiotics are prescribed at incredibly high rates in this country. That’s the big picture, and it’s clear that it’s a problem, but what’s the pragmatic translation? The small picture is something more like a baby who’s been screaming for days and a scared parent who needs to know, just how hard should we resist antibiotics, and in what situations?

We’re starting with perhaps the most difficult question. But you see, in the United States, in order to get antibiotics, you need a prescription. And that means it’s really up to the doctor. And because everyone has thought that antibiotics are ‘free,’ there has been a tendency by both doctors and parents to over-prescribe them and to over-want them. But once you start assigning a cost to them, then the situation changes. And so for parents, I advise them that when their child is sufficiently sick, that they should seek medical attention, and they should try to ensure that the doctor — and that’s shorthand for doctor, nurse, nurse practitioner, physician’s assistant — that the doctor do a careful exam. And then if the doctor says your child does not need an antibiotic, that parent should be relieved. Not thinking, ‘Why is my child deprived?’

But isn’t it so often unclear whether antibiotics are actually needed?

It is unclear, and in fact we know that most of the upper respiratory and ear infections that children have are caused by viruses that don’t even respond to antibiotics. As I write in my book, in the U.S. in 2010, there were 258 million courses of antibiotics prescribed. That’s five courses for every six people. So point number one is that that’s a lot. Point number two is that there’s enormous regional variation — variation that cannot be explained based on variation in the prevalence of different bacterial infections. So that means that it’s a function of how medicine is practiced. And the practice of medicine involves both the doctors and the patients. Both are parties. And what I point out is that in Sweden, where the people are at least as healthy as we are, at every age they’re using 40 percent of the antibiotics that we’re using. And that means, across the board, that 60 percent of the antibiotics are unnecessary. And that’s at every age, not just in childhood –though it’s especially important in childhood at every age. Continue reading

Psychobiotics: Can Stomach Bacteria Change Your Brain?

The plot keeps thickening when it comes to the connection between your gut and your brain.

A new review article links probiotics to changes in mood and mental health, suggesting these “good” bacteria might have potential as a treatment for depression and other psychiatric maladies. In the study, published in the journal Biological Psychiatry, researchers define the term “psychobiotic” as “a live organism that, when ingested in adequate amounts, produces a health benefit in patients suffering from psychiatric illness.”



These organisms act on what researchers call the “brain-gut axis,” a biological network connecting the intestinal and endocrine systems to the spinal cord and regions in the brain that process stress, such as the HPA-axis.

Is all this plausible? Perhaps. Ghrelin, known as the “hunger hormone” and produced in the intestines, was recently found to play a role in the development of chronic stress. And stress in turn has been found to alter our microbiota. There’s growing evidence that there’s a special connection between the gut and the brain, and as one MGH psychiatrist said recently: “There is a neural feedback from the gut to the brain so chronic gastrointestinal distress can exacerbate anxiety or depression.”

Thomas Insel, Director of the National Institute of Mental Health, stated last December that how “differences in our microbial world influence the development of brain and behavior will be one of the great frontiers of clinical neuroscience in the next decade.”

Dr. Timothy Dinan of University College Cork in Ireland and the psychobiotic study’s lead author says that although the research conducted on humans is sparse, “the animal studies indicate that certain psychobiotics can change brain chemistry.”

Continue reading

Mass. General Studies Probiotics For Irritable Bowel Syndrome and Depression

Irritable Bowel Syndrome seems like an obvious target for a study of probiotics; the “benevolent” bacteria are known to affect the chemistry of the gut.

But depression? Does this fit into the thinking that the gut is kind of a second brain??

Anyway, this from MGH:

BOSTON (November 23, 2010) —A new clinical trial is underway at the Massachusetts General Hospital to assess the safety and efficacy of the probiotic bacteria GanedenBC30 (Bacillus coagulans GBI-30, 6086) in outpatients with irritable bowel syndrome (IBS) and major depressive disorder (MDD). This research is believed to be the first of its kind to examine common factors underlying both gut and psychiatric disorders and the use of probiotics as an intervention in depression.

Details and the rationale behind the study are here. The study’s lead researcher notes that there’s such a huge overlap between Irritable Bowel Syndrome and psychiatric disorders that “it is perhaps more than just coincidental.”

Probiotics are certainly trendy. They’re showing up in everything from yoghurt to supplement powders. Some studies show some benefits — this review found that probiotics shortened the duration of diarrhea. But this assessment of yoghurt claims by the Center for Science in the Public Interest suggests that some of the benefits — at least as touted in food ads and labeling — may be overstated.

Daily Rounds: Health Insurance Profits Soar; Fosamax Questions; Probiotics For Diarrhea; Public Against Obamacare Repeal; Menino Fights For Insurance Flexibility

Health Insurance Profits Soar, Dem Calls For Rebates “Health insurance profits are skyrocketing in 2010 compared to last year’s returns and the outgoing chairman of the House subcommittee that oversees the companies is calling on them to return the profits to consumers in the form of premium reductions.” (Huffington Post)

Fosamax Lawsuits Question Wide Use of Osteoporosis Drugs – “The trial is providing a palpable backdrop for a broadening debate among many doctors and researchers who are rethinking Fosamax and similar bone medications known as oral bisphosphonates, particularly as a treatment for women who have not yet developed osteoporosis.” (The New York Times)

Medical News: Probiotics May Help Treat Acute Diarrhea – in Infectious Disease, General Infectious Disease from MedPage Today “One way to battle diarrhea-causing gut bugs is to introduce even more gut bugs, two major reviews found.” (

Poll: Public mixed on GOP tax, health plans – “When it comes to the health care law Obama signed in March, just 39 percent back the GOP effort to repeal it or scale it back. Fifty-eight percent would rather make even more changes in the health care system or leave the measure alone.” (Boston Herald)

Menino seeks more control over health insurance costs – The Boston Globe “Mayor Thomas M. Menino vowed yesterday to go to Beacon Hill to fight for a state law that would allow the city of Boston to save millions of dollar on health care insurance. Tweet Be the first to Tweet this! Yahoo! BuzzShareThis Menino said he could save at least $12 million a year if he gained the authority to shift a larger share of the city’s insurance costs from taxpayers to teachers, police, firefighters, and other city employees, retirees, and elected officials.” (Boston Globe)