Americans are exposed to anywhere from 10 to 20 different types of antibiotics during childhood, which can reduce our resistance to the medications and decrease our ability to fight off certain antibiotic-resistant infections. This overexposure may also lead to our concurrent rise in obesity, diabetes, allergies and asthma according to new research published in the journal Nature.
Dr. Martin Blaser, lead researcher in the study and a microbiologist at New York University suggests that bacterial colonies, especially within the human digestive tract, have drastically changed over the last century. Bacteria vital for proper digestion, metabolizing of key nutrients and fighting infection have dramatically decreased in the last 80 to 100 years—coinciding with the rise in antibiotic use.
As key bacteria die off (often the side-effect of using antibiotics to kill harmful pathogens), Blaser says those helpful flora colonies may never recover, leaving the body open to diseases such as asthma and allergies and digestive disorders. Two hormones produced by the stomach (leptin and ghrelin) were noted to exhibit different behaviors in the absence of certain bacteria once much more prevalent in the stomach than found today. These hormones are critical in alerting the brain that the body is hungry, and, according to Blaser, could be misfiring as a result of bacterial imbalances, giving off false signals and ultimately leading to diseases such as diabetes and obesity.
It might not just be the over prescribed antibiotics to blame; livestock raised on U.S. soil were fed some 29 million pounds of antibiotics in 2009—more than 80 percent of all antibiotics used in the U.S.
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