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Overuse of the drugs seems to make us gain weight—even when we don't take them.
Doctors in Newport, Rhode Island, had to change one of their policies last year because they inadvertently made a young woman obese. At least, because they believe they possibly did.
A few months beforehand, the 32-year-old mother, who had never before been obese, had developed a vaginal infection. She took an antibiotic and, as expected, the infection went away. But shortly after, the woman’s stomach began to ache. A test of her stool found the presence of a lethal toxin.
We've long known that taking an antibiotic can inadvertently lead to another infection. In this case, it was an overgrowth of the bacterium Clostridium difficile in the woman’s colon. C. difficile is an opportunist that can exist in harmony with the other bacteria in our guts; it’s only when that ecosystem is disrupted that C. difficile takes over and becomes deadly. It releases a toxin (which is actually a relative of the toxin sold as Botox, or Clostridium botulinum toxin) that causes a person’s bowels to decay and expand and rupture, and the person dies. Last year in the U.S. alone, C. difficile killed 15,000 people. Most of the cases were precipitated by treatment with an antibiotic.
To escape this fate, the Rhode Island woman began treatment to kill the C. difficile, with another antibiotic. She also tested positive for another bacterial infection of the stomach, Helicobacter pylori. So the doctors treated her with two additional antibiotics. Despite all of this, her condition deteriorated.
In a last-ditch attempt to restore balance to her intestinal flora, her doctors recommended a fecal transplant, the technical term for the vogue medical procedure that is simply putting one person’s feces into another person. The idea is that the transplanted feces will populate the sick person’s bowels with a healthy bacterial population. At the request of the patient, the Newport doctors did not use a “professional” stool donor, but instead utilized the excreta of the woman’s 16-year-old daughter.
The transplant was a success, in that the woman’s symptoms went away. The bacterial ecosystem finally appeared to be restored to some kind of order. But they also seemed to have brought something else along. The woman’s daughter was obese, and in the months after the transplant, the patient gained 34 pounds, qualifying her as obese for the first time in her life.
“This case serves as a note of caution,” her gastroenterologists later wrote a medical-journal report. “We recommend selecting non-overweight [fecal] donors.”
Of course, many things could have caused her weight gain. Treatment of Helicobacter pylori, the bacteria that causes most ulcers, is itself associated with weight gain. Infectious-disease specialists at Massachusetts General Hospital Elizabeth Hohmann and Ana Weil noted at the time that “it is possible and perhaps even likely that the weight gain in the case reported was influenced not only by microbial communities transmitted during [fecal transplant], but also by genetic factors.”
In a randomized controlled trial of the reverse scenario, where overweight people with metabolic syndrome underwent fecal transplants from lean donors, recipients showed improvement in their degrees of insulin resistance. Taken together with other research on the effects of gut microbes on body weight and metabolism, Hohmann and Weill concluded in the same journal: “These studies take the concept of ‘you are what you eat’ to breathtaking new heights and certainly should stimulate further study!”
Of course, most people who are overweight have not had a fecal transplant. Most people will never need a fecal transplant. But the idea that a person can essentially contract obesity because of a change in gut microbes is at once exciting and unnerving—because exposure to microbe-altering drugs in day-to-day life has become almost inevitable. This month, the U.S. Food and Drug Administration quietly released a report that said over the past year, antibiotics sold annually for use in food animals increased to 33,860,000 pounds.
That’s a 22 percent increase since five years prior (which was the first time the amount was even measured). Usage also increased in 2014 alone, despite several prominent food producers and restaurants like Whole Foods and Chipotle swearing off antibiotic-raised animal products. Most of those antibiotics are “medically important,” meaning they are used in humans to treat diseases. But a majority of antibiotics are not absorbed by the animal, just excreted. So even those that are not medically important manage to find their ways into soil and water as they become part of the 18 gallons of manure that every cow produces every day.
Antibiotics in manure that seep into soil have been detected in carrots, lettuce, and green onions. Some antibiotics remain active for months after passing through the animal and are detectable in rivers miles from their use; a study of a river in Colorado found several antibiotics everywhere except for “a pristine site in the mountains before the river had encountered urban or agricultural landscapes.” Antibiotic overuse turned the Hudson River into a breeding ground for drug-resistant bacteria.
Antibiotics do, of course, save many lives in the appropriate medical context. But in animals, antibiotics are rarely given to treat illness. They are given blindly to entire populations to prevent possible infections—which is never indicated medically. Even less medically warranted—actually contrary to the interest of the animal—antibiotics are given as appetite and growth stimulants. In the 1950s, shortly after the advent of modern antibiotics, ranchers noticed that cattle that were treated for infections would put on weight. Because ranchers are paid by the pound, rather than by the number of cattle sold, the idea had appeal. By the 1970s, blanket administration of antibiotics to promote growth became common practice.
Because people so enjoy eating meat and cheese for various reasons—note the 76 million Facebook users who will watch when Buzzfeed posts a video of a pepperoni grilled-cheese sandwich or the 108 million who watch the bacon-wrapped grilled-cheese sandwich—animals must be quickly grown to great sizes in order to accommodate the demand for meat that will serve a planet of 7 billion humans. As that number approaches 8 and then 9 billion, the need for antibiotics in meat production will be only greater. And despite the fact that ranchers have known for decades that antibiotics cause their animals to gain weight, the idea that this has a similar effect on people is somehow just now seeping into the heads of everyone else.
* * *
Only in the last few years have we begun to understand the extent of the effects of the microbes inside us on our health—or, rather, as being a part of our health. As the microbiologists Rob DeSalle and Susan Perkins write in their new book Welcome to the Microbiome, “It’s not the microbes that cause problems with our health, but rather disruptions in the natural ecology of our bodies that lead to illness. It is only when the co-evolved ecological balance of our body’s cells with the trillions of microbes living in and on us is thrown out of whack that pathogenicity [disease] arises.”
This may be the first time that the word pathogenicity has been used in the same sentence as whack. Scientists are still figuring out how to talk about all of this. It was only recently that DNA-sequencing technology allowed them to learn that there are indeed trillions of microbes inside each of us, and that in the absence of pathogenicity, the microbiome keeps us healthy every minute of every day, playing significant roles in digestion and assembly of nutrients and vitamins.
The idea is only very recently hitting mass audiences. If you’ve ridden a subway in New York this month, you’ve seen an ad for a new exhibit about the microbiome at the American Museum of Natural History called “The Secret World Inside You.” DeSalle and Perkins are the curators. Of all things bodily that could belong in a natural history museum, the microbiome makes the most obvious case for itself. The species that live inside us are older than humans by millennia. Dinosaurs had microbiomes. And our internal ecosystems—the ecosystems that we are—have been dramatically affected by the food and drugs we put into the natural world and, directly or indirectly, back into ourselves.
One of the first people Perkins took through the exhibit was a student of hers from Berlin. “When she learned that 70 percent of the antibiotics in the U.S. go to farm animals,” Perkins recalled, “she said she’s never eating American meat again.”
The German student was apparently unaware that antibiotics are widely used in German agriculture, too.
Does Exposure to Antibiotics Cause Weight Gain? It Seems To - The Atlantic
Doctors in Newport, Rhode Island, had to change one of their policies last year because they inadvertently made a young woman obese. At least, because they believe they possibly did.
A few months beforehand, the 32-year-old mother, who had never before been obese, had developed a vaginal infection. She took an antibiotic and, as expected, the infection went away. But shortly after, the woman’s stomach began to ache. A test of her stool found the presence of a lethal toxin.
We've long known that taking an antibiotic can inadvertently lead to another infection. In this case, it was an overgrowth of the bacterium Clostridium difficile in the woman’s colon. C. difficile is an opportunist that can exist in harmony with the other bacteria in our guts; it’s only when that ecosystem is disrupted that C. difficile takes over and becomes deadly. It releases a toxin (which is actually a relative of the toxin sold as Botox, or Clostridium botulinum toxin) that causes a person’s bowels to decay and expand and rupture, and the person dies. Last year in the U.S. alone, C. difficile killed 15,000 people. Most of the cases were precipitated by treatment with an antibiotic.
To escape this fate, the Rhode Island woman began treatment to kill the C. difficile, with another antibiotic. She also tested positive for another bacterial infection of the stomach, Helicobacter pylori. So the doctors treated her with two additional antibiotics. Despite all of this, her condition deteriorated.
In a last-ditch attempt to restore balance to her intestinal flora, her doctors recommended a fecal transplant, the technical term for the vogue medical procedure that is simply putting one person’s feces into another person. The idea is that the transplanted feces will populate the sick person’s bowels with a healthy bacterial population. At the request of the patient, the Newport doctors did not use a “professional” stool donor, but instead utilized the excreta of the woman’s 16-year-old daughter.
The transplant was a success, in that the woman’s symptoms went away. The bacterial ecosystem finally appeared to be restored to some kind of order. But they also seemed to have brought something else along. The woman’s daughter was obese, and in the months after the transplant, the patient gained 34 pounds, qualifying her as obese for the first time in her life.
“This case serves as a note of caution,” her gastroenterologists later wrote a medical-journal report. “We recommend selecting non-overweight [fecal] donors.”
Of course, many things could have caused her weight gain. Treatment of Helicobacter pylori, the bacteria that causes most ulcers, is itself associated with weight gain. Infectious-disease specialists at Massachusetts General Hospital Elizabeth Hohmann and Ana Weil noted at the time that “it is possible and perhaps even likely that the weight gain in the case reported was influenced not only by microbial communities transmitted during [fecal transplant], but also by genetic factors.”
In a randomized controlled trial of the reverse scenario, where overweight people with metabolic syndrome underwent fecal transplants from lean donors, recipients showed improvement in their degrees of insulin resistance. Taken together with other research on the effects of gut microbes on body weight and metabolism, Hohmann and Weill concluded in the same journal: “These studies take the concept of ‘you are what you eat’ to breathtaking new heights and certainly should stimulate further study!”
Of course, most people who are overweight have not had a fecal transplant. Most people will never need a fecal transplant. But the idea that a person can essentially contract obesity because of a change in gut microbes is at once exciting and unnerving—because exposure to microbe-altering drugs in day-to-day life has become almost inevitable. This month, the U.S. Food and Drug Administration quietly released a report that said over the past year, antibiotics sold annually for use in food animals increased to 33,860,000 pounds.
That’s a 22 percent increase since five years prior (which was the first time the amount was even measured). Usage also increased in 2014 alone, despite several prominent food producers and restaurants like Whole Foods and Chipotle swearing off antibiotic-raised animal products. Most of those antibiotics are “medically important,” meaning they are used in humans to treat diseases. But a majority of antibiotics are not absorbed by the animal, just excreted. So even those that are not medically important manage to find their ways into soil and water as they become part of the 18 gallons of manure that every cow produces every day.
Antibiotics in manure that seep into soil have been detected in carrots, lettuce, and green onions. Some antibiotics remain active for months after passing through the animal and are detectable in rivers miles from their use; a study of a river in Colorado found several antibiotics everywhere except for “a pristine site in the mountains before the river had encountered urban or agricultural landscapes.” Antibiotic overuse turned the Hudson River into a breeding ground for drug-resistant bacteria.
Antibiotics do, of course, save many lives in the appropriate medical context. But in animals, antibiotics are rarely given to treat illness. They are given blindly to entire populations to prevent possible infections—which is never indicated medically. Even less medically warranted—actually contrary to the interest of the animal—antibiotics are given as appetite and growth stimulants. In the 1950s, shortly after the advent of modern antibiotics, ranchers noticed that cattle that were treated for infections would put on weight. Because ranchers are paid by the pound, rather than by the number of cattle sold, the idea had appeal. By the 1970s, blanket administration of antibiotics to promote growth became common practice.
Because people so enjoy eating meat and cheese for various reasons—note the 76 million Facebook users who will watch when Buzzfeed posts a video of a pepperoni grilled-cheese sandwich or the 108 million who watch the bacon-wrapped grilled-cheese sandwich—animals must be quickly grown to great sizes in order to accommodate the demand for meat that will serve a planet of 7 billion humans. As that number approaches 8 and then 9 billion, the need for antibiotics in meat production will be only greater. And despite the fact that ranchers have known for decades that antibiotics cause their animals to gain weight, the idea that this has a similar effect on people is somehow just now seeping into the heads of everyone else.
* * *
Only in the last few years have we begun to understand the extent of the effects of the microbes inside us on our health—or, rather, as being a part of our health. As the microbiologists Rob DeSalle and Susan Perkins write in their new book Welcome to the Microbiome, “It’s not the microbes that cause problems with our health, but rather disruptions in the natural ecology of our bodies that lead to illness. It is only when the co-evolved ecological balance of our body’s cells with the trillions of microbes living in and on us is thrown out of whack that pathogenicity [disease] arises.”
This may be the first time that the word pathogenicity has been used in the same sentence as whack. Scientists are still figuring out how to talk about all of this. It was only recently that DNA-sequencing technology allowed them to learn that there are indeed trillions of microbes inside each of us, and that in the absence of pathogenicity, the microbiome keeps us healthy every minute of every day, playing significant roles in digestion and assembly of nutrients and vitamins.
The idea is only very recently hitting mass audiences. If you’ve ridden a subway in New York this month, you’ve seen an ad for a new exhibit about the microbiome at the American Museum of Natural History called “The Secret World Inside You.” DeSalle and Perkins are the curators. Of all things bodily that could belong in a natural history museum, the microbiome makes the most obvious case for itself. The species that live inside us are older than humans by millennia. Dinosaurs had microbiomes. And our internal ecosystems—the ecosystems that we are—have been dramatically affected by the food and drugs we put into the natural world and, directly or indirectly, back into ourselves.
One of the first people Perkins took through the exhibit was a student of hers from Berlin. “When she learned that 70 percent of the antibiotics in the U.S. go to farm animals,” Perkins recalled, “she said she’s never eating American meat again.”
The German student was apparently unaware that antibiotics are widely used in German agriculture, too.
Does Exposure to Antibiotics Cause Weight Gain? It Seems To - The Atlantic