"In 2002 Americans were about an inch taller and 24 pounds heavier than they were in the 1960s, and more than a third are now classified as obese," Kennedy writes. "Of course, diet and lifestyle are prime culprits. But some scientists wonder whether there could be other reasons for this staggering transformation of the American body. Antibiotics might be the X factor—or one of them."
"Of course, while farm animals often eat a significant dose of antibiotics in food, the situation is different for human beings," Kennedy writes. "By the time most meat reaches our table, it contains little or no antibiotics. So we receive our greatest exposure in the pills we take, rather than the food we eat. American kids are prescribed on average about one course of antibiotics every year, often for ear and chest infections. Could these intermittent high doses affect our metabolism?"
Martin J. Blaser, the director of the Human Microbiome Program and a professor of medicine and microbiology at New York University, is studying the effects of antibiotics on the growth patterns of baby mice. Mixing high-calorie diets with antibiotics has resulted in huge weight gains, particularly among the female mice, Kennedy writes. Blazer wrote: "The observations are consistent with the idea that the modern high-calorie diet alone is insufficient to explain the obesity epidemic and that antibiotics could be contributing.” (Read more)