Among the many questions that arise when we take a serious look at modern health and medicine, there are at least two questions with no easy answers:
Are we taking too many antibiotics and heading toward a crisis involving antibiotic-resistant superbugs?
And what’s driving the ever-worrisome obesity rate -- is it poor nutrition, the poverty rate, lack of exercise, the way food is produced?
These two issues dovetail in the research of Dr. Martin Blaser of New York University’s Langone Medical Center, who is studying a possible link between antibiotics and obesity.
Blaser, a professor of microbiology, recently focused on the changes in the gut bacterial environment -- the microbiome -- whenever antibiotics are prescribed for Helicobacter pylori.
The bacterium H. pylori can reside in our gut and cause no harm. But it’s not unusual for doctors to prescribe antibiotics to eradicate it, for fear that an H. pylori infection will lead to a gastrointestinal ulcer.
Blaser urged caution in automatically assuming H. pylori is a “bad” bacteria. His researchers found changes in the gut microbiome in the presence of antibiotics for H. pylori.
The problem was the hunger hormone ghrelin, which is supposed to fall after a meal. Instead, when H. pylori was gone, ghrelin stayed steady -- and that became a signal for the brain to keep eating.
Researchers at NYU also studied mice who were given dosages of antibiotics similar to what children typically get for ear infections. The mice had more body fat than the control group, even though both groups of mice had the same diet.
Last year, when Blaser published an editorial on the overuse of antibiotics, ABCNews.com caught up to him for a comment:
“Antibiotics are miraculous,” he said. “They’ve changed health and medicine over the last 70 years. But when doctors prescribe antibiotics, it is based on the belief that there are no long-term effects. We’ve seen evidence that suggests antibiotics may permanently change the beneficial bacteria that we’re carrying.”
Thanks to a National Institutes of Health grant, Blaser will continue to study the human microbiome and possible associations with the current obesity epidemic. He and other scientists with NIH funding want to track the diversity and characteristics of microbial communities. The human gut alone contains billions of bacteria.
“I know I am now doing the most important work of my career,” Blaser recently told the New York Times.
Various studies around the world are looking at the human microbiome and the role of bacteria in conditions as wide-ranging as allergies, asthma, diabetes and inflammatory bowel disease. Does bacteria have an impact on obesity? It will be interesting to find out.
Sources:
Murphy, Kate. “In Some Cases, Even Bad Bacteria May Be Good.” The New York Times. Web. 2 Jan. 2012. http://www.nytimes.com/2011/11/01/health/scientist-examines-possible-link-between-antibiotics-and-obesity.html?_r=1
Moisse, Katie. “Antibiotics Could Be Driving Up Obesity.” ABCNews.com. Web. 2 Jan. 2012. http://abcnews.go.com/blogs/health/2011/11/01/antibiotics-could-be-driving-up-obesity
Reviewed January 3, 2012
by Michele Blacksberg RN
Edited by Jody Smith