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From Nature magazine
Bacteria living naturally within the gut provide a gateway to flab, according to a few reports this week. These bacteria may explain how antibiotics fatten farm animals and perhaps people too, and how certain genes predispose organisms to obesity.
In a study published 22 August in Nature, researchers mimicked what farmers have been doing for decades to fatten up their livestock: they fed young mice a steady low dose of antibiotics. The antibiotics altered the composition of bacteria in the guts of the mice and also changed how the bacteria broke down nutrients. The bacteria in treated mice activated more genes that turn carbohydrates into short-chain fatty acids, and they turned on genes related to lipid conversion in the liver. Presumably, these shifts in molecular pathway enable fat build-up. Just as farm animals get fat, the antibiotic-fed mice put on weight.
Martin Blaser, a microbiologist at New York University in New York, says that parents might unknowingly be promoting a similar phenomenon when they treat common ailments and ear infections in their children. To back that idea up, he points to another study he authored. The study, published on 21 August, found that a disproportionate number of 11,000 kids in the United Kingdom who were overweight by the time they were 3 years old had taken antibiotics within their first 6 months of life.
“Antibiotics are extremely important drugs,” Blaser says, “but especially when given early in life, I believe they come at a cost that parents, doctors and patients should be aware of.”
Microbes also seem to be an accomplice in genetically induced pudginess, according to a study published today in Nature Immunology. When researchers rid mice of a gene encoding a gut molecule called lymphotoxin, segmented filamentous bacteria overwhelmed the normal microbial community. These bacteria may gobble up excess fat like tapeworms — the mice remained thin no matter what they ate. What’s more, mice with lymphotoxin intact were able to keep their slim figures when the researchers implanted the segmented filamentous bacteria in their guts.
Although the papers provide tantalizing links, Peter Turnbaugh, a microbiologist at Harvard University in Cambridge, Massachusetts, says that there’s more work to be done before microbes enter the limelight in the fight against obesity. “These studies suggest mechanisms by which different bacteria promote adiposity, but they don’t fully define pathways,” he says. “What really excites me about these papers is that now we have two new mouse models to do the follow-up experiments.”
This article is reproduced with permission from the magazine Nature. The article was first published on August 27, 2012.
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9 Comments
Add CommentGood jobs thx :)
Reply | Report Abuse | Link to thisI started out with a dose of pneumonia, at three, almost terminated me If it hadn't been for Dr. Wray Ridge (chief of staff at Hamilton (ON) General, and his buddy, the developer of Sulfa Drugs, I wouldn't be here, and evidently it weakened my immune system, so that for the next12 years, I was almost always half ill, and missed much schooling. I had a nose that dripped all the time, and would usually go through at least four hankies per day.
Reply | Report Abuse | Link to thisMy father was a minister, and so the local doctors supplied 'free' antibiotics, usually drug samples. So I always had medication, which 'cured' me temporarily.
When my beard sprouted, I cultivated a mustache, so that my upper lip wouldn't always be red and sore.
I started smoking at majority, which seemed to cure my hayfever (about 100 allergies), and my weight remained stable, but at 33, I abruptly quit, and my weight started to climb, not fast, because my business kept me hopping.
Now a 76, I am obese. All the antibiotics over all those years, plus the habit formed by chewing on a pipestem, and always snacking afterwards, doubtless caused my weight gain, eh?
well
Reply | Report Abuse | Link to thisThe far reaching implications of the microbiome are just coming into our awareness. The eradication of the ulcer causing bacteria H pylori has been implicated in increased levels of the "hunger hormone" ghrelin, which may also contribute to the obesity crisis. See http://bit.ly/NGAWuL for a cursory review of the broader implications of our micro-biotic partners in live. Its hard to imagine, but even our mood seems to be affected by bacteria.
Reply | Report Abuse | Link to thisI've had a weight problem since I was 7 years old. I have also been warned to never take penicillin. I ordered my medical records. Wouldn't that be some real *(*& if my weight problem had been caused by antibiotics? I was 150pds by 3rd grade~~ the torment I received my entire life was relentless and punishing and I could never lose weight, it was like my metabolism was broken. This is exactly why we need a new form of medical services --- 300 yrs of western medicine isnt good enough for me or my son. Anti-biotic is a screwed up word anyways, it literally means to mess up your biotic structures through your body. Thank you scientists for all the years of hate and abuse from being overweight. Maybe we should stop giving anti biotics and give probiotics.
Reply | Report Abuse | Link to thisdesireegrooms - Are you saying it would be better if all the millions saved from childhood diseases had died? Would it have been better if you had died of whatever you were treated for? Don't blame the doctors or scientists, they gave you and many millions more the opportunity to grow into productive adults. What you do with that opportunity is on you. The drugs are not perfect, they are improved all the time, and they are often prescribed unnecessarily, but they have changed the world.
Reply | Report Abuse | Link to this70 % of all antibiotics get fed to industrial farm animals, including farmed fish! As long as we are eating those we invariably MUST end up with these dire health problems caused by this. ( from Golden Staph to bird flu, and now obesity, too.)
Reply | Report Abuse | Link to thisFuture generations could well resort to suing their parents for child abuse-for mal-feeding them, and their doctors, for maltreating them with the wrong drugs that wiped out their immune system.
It has been shown that MacDonalds and their ilk are not easy to sue for health reasons, but it is relatively easy for us to vote with our feet, and resort to such medically proven anti-virals and antibiotics like garlic, and probiotics, like kombucha.
We did, and haven't looked back since.
youthevity.com
Interesting stuff. Last year I had a systemic MRSA infection, and had 4 months of IV antibiotics, and have been on a 2x/day dose of minocycline since mid January to prevent reoccurrence. Since January I have put on 35 pounds without altering my eating habits. I started a low carb diet 11 days ago. After reading the article, I am hopeful that the absence of carbs will short-circuit the effect. I'm going to take a copy of this to my ID doctor at my next follow up visit.
Reply | Report Abuse | Link to thisWow@J in the Lou... We share very similar stories, I had HA-Mrsa and was blasted with the vancomycin coctail via IV for four weeks. I had major damage done to both of legs because of multiple abcesses. Then of course, had another massive dose for three weeks when I returned home. It seemed like I had put on 45 pounds, like overnight... No one warned me about this potential side effect, nor how to reverse it.
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