Microbes made me do it

August 13, 2006 2:35 PM

Can microbes make us fat? Of the trillions and trillions of cells in a typical human body — at least 10 times as many cells in a single individual as there are stars in the Milky Way — only about 1 in 10 is human. The other 90 percent are microbial. These microbes — a term that encompasses all forms of microscopic organisms, including bacteria, fungi, protozoa and a form of life called archaea — exist everywhere. New evidence suggests microbes in our bodies can determine how efficiently we process food and affect our hunger centers.
posted by caddis (29 comments total)

Not to derail the obesity focus of this article, but the fact that we are only 10% human also explains a lot of our existential angst.
posted by kozad at 2:44 PM on August 13, 2006 [2 favorites]

I have personal experience with this. After a round of major antibiotics during recuperation from a life-threatening head injury my digestion has never been the same. The best thing about it? My farts generally — I am serious! — do not stink. Whatever bacteria produces the nasty, evil smells that, say, my wife emits, I do not possess. Which, frankly, makes us both happy.

This is more than you wanted or needed to know, I'm sure.
posted by five fresh fish at 2:44 PM on August 13, 2006 [2 favorites]

H. pylori lead to ulcers and Toxoplasma gondii (pdf) can affect thought and decision. Back pain appears to be treatable with antibiotics in some instances. Microbes appear to affect us far more than to just make us ill.
posted by caddis at 2:44 PM on August 13, 2006

We're 10% human in terms of cellular DNA counts. What percentage of us is human in terms of weight, energy consumption, and suchlike?
posted by five fresh fish at 2:45 PM on August 13, 2006

If some microbes can make us fat, can others make us thin? I don't mean like cholera, more something like what's described here, but it makes it hard to gain weight.
posted by owhydididoit at 3:06 PM on August 13, 2006

I don't like the idea that I might have a 'borg collective' like community of microbes in my stomach. Resistance is futile I guess...
posted by alteredcarbon at 3:18 PM on August 13, 2006

I can't tell you how happy it makes me to see an article about obesity that includes photos that aren't stock photos of big bellies and butts. Well done, NYT.
posted by ferociouskitty at 3:20 PM on August 13, 2006

IT'S THE FAT THAT MAKES YOU FAT!
posted by Captaintripps at 3:21 PM on August 13, 2006

Fascinating article by Robin Marantz Henig . I also like her article about lie detection.

I think Dr. Richard Atkinson is on to something significant. He has a test for the "obesity virus".
posted by nickyskye at 3:27 PM on August 13, 2006

Terror Cells.
posted by blue_beetle at 3:32 PM on August 13, 2006 [1 favorite]

Not to derail the obesity focus of this article, but the fact that we are only 10% human also explains a lot of our existential angst.

Bacteria are much smaller then Eukaryotic cells, such as human ones. I think the 10% is in count, but obviously not volume.
posted by delmoi at 3:48 PM on August 13, 2006

Guys, do these microbes make my butt look big?

(Nice article, caddis, thanks!)
posted by rmless at 4:00 PM on August 13, 2006

The Atkinson Diet - limit your microbe intake.
posted by Bort at 4:20 PM on August 13, 2006

The Atkinson Diet

Funny!
posted by nickyskye at 4:21 PM on August 13, 2006

I'm not fat, it's my microbes.
posted by nyxxxx at 4:28 PM on August 13, 2006

The factoid that begins this is highly deceptive. Virtually all of those bacteria are prokaryotes; they're tiny and carry very little genetic information. Our cells are eukaryotic; they're huge (by comparison) and have an immense amount of genetic information. (Most of which is junk, but...)

The vast majority of the bacteria they're referring to are symbiotic bacteria in our large intestines.

We're 10% human in terms of cellular DNA counts.

No, we're probably greater than 98% human in terms of DNA count because prokaryotes have so little DNA compared to us. (And arguably the contents of the large intestine is "outside" and can't be considered to actually be part of us.)

As to whether it's possible for bacteria to affect us in various ways, there's good evidence that they can. (Certainly they're able to kill us.) I don't think there's anything particularly profound about that.
posted by Steven C. Den Beste at 4:32 PM on August 13, 2006

So maybe the real reason why exercise allegedly works is cuz if you move around a lot, all the microbes in your body either get dizzy and confused and then die, or they say hang it all and head out the nearest sweat gland or bunghole. Sort of a "there goes the neighborhood" kinda thing when you decide to start eating right and exercise.

So if we could just come up with a machine that causes the microbes to dive for the nearest airlock without actually exercising...!
posted by ZachsMind at 4:35 PM on August 13, 2006 [1 favorite]

Time to insert the special ops team again...
posted by cenoxo at 6:10 PM on August 13, 2006

And arguably the contents of the large intestine is "outside" and can't be considered to actually be part of us.

Cool. I hadn't thought of/come across that.
posted by Heywood Mogroot at 6:33 PM on August 13, 2006

And arguably the contents of the large intestine is "outside" and can't be considered to actually be part of us.

We are deuterostomes, we are a tube within a tube. What is to say that we did not succeed based on the environment created inside of the inner tube. While our intestinal flora is not part of us, it contributes to our success; just as our mastery of agriculture, heating, electricity and waste-water treatment are not part of us, they contribute to our ability to flourish in our environment.

Don't be so quick to write off the microbes, just because they are not a part of us on a cellular level does not mean that they are not a driving force in human development.
posted by peeedro at 7:03 PM on August 13, 2006

And arguably the contents of the large intestine is "outside" and can't be considered to actually be part of us.

Or not.
posted by owhydididoit at 7:27 PM on August 13, 2006

So... can they make us fat? Candida are a yeast that can take over our digestive system (large intestines) when we take antibiotics that kill all of the bacteria with antibiotics, bacteria that normally keep the yeast in check. This causes your tongue to be slightly white (thrush), and in women can cause a higher incident of yeast infections which is really just an overgrowth of the naturally occurring candida in our system. Candida is a yeast, so everytime we eat sugar, it thrives. An overgrowth of candida according to many naturopathic doctors, can make you crave sugar, and we all know eating too much sugar can make you fat.
posted by Summer1158 at 7:51 PM on August 13, 2006

and we all know eating too much sugar can make you fat.

Whoa. Say that AGAIN?

Sugar makes you fat? Yeah. Goddamn it! It all seems so obvious now.

I've cut out sugar and microbes. Thin awesome-sexxiness here I come!








...hmmm. Nothing yet. How long is this supposed to take?
posted by tkchrist at 7:59 PM on August 13, 2006

The Atkinson Diet - limit your microbe intake.

Heh - but sometimes it's beneficial to increase your microbial intake, ie., lactobaccilis from yogurt. By introducing a lot of benign bacteria, there's the chance that they'll outcompete the bacteria that produce noxious metabolic waste or those that might be a little *too* good at breaking down food that our digestive system can't.

I've had a similar experience as five fresh fish only the antibiotics killed off a good chunk of my benign microfloral symbiote and the nasty bugs took over (my digestive system was not happy). Yogurt and these citrus-ey-yoghurt-ey-asian drinks returned me to normal quickly.
posted by porpoise at 8:26 PM on August 13, 2006

http://www.askdrsears.com/html/8/T080400.asp
In case yogurt isn't your thing... taking ACIDOPHILUS works too.
posted by Summer1158 at 8:56 PM on August 13, 2006

I've had a similar experience as five fresh fish only the antibiotics killed off a good chunk of my benign microfloral symbiote and the nasty bugs took over (my digestive system was not happy). Yogurt and these citrus-ey-yoghurt-ey-asian drinks returned me to normal quickly.

Second time it's happened to me (keflex the first time and I think it's the only reason the amox caused so much trouble this time) and the yogurt's not working so well this time.
posted by IronLizard at 10:08 PM on August 13, 2006

Oh good... so to all those pithy naggers rabbiting on about too much intake and too little exercise, I can finally smile through a mouthful of powdered sugar and wave around a copy of this research -- "Hah! It's not my fault! It's the microbes, dammit. Outta my hands. Say... are you going to finish those pancakes or just leave them on your plate?"
posted by Mike D at 7:07 AM on August 14, 2006

Very interesting. There was an Atlantic article 4-5 years ago suggesting that bacteria and viruses might have a hand in all sorts of human illness, including some cancers. We are really at the beginning of understanding all this, aren't we?

There is one thing that does not make sense to me though. If obesity is a communicable disease, why has it skyrocketed in the last few decades? Were these viruses not around in say, 1900, when only a tiny portion of the population was obese?
posted by LarryC at 8:34 AM on August 15, 2006

Were these viruses not around in say, 1900, when only a tiny portion of the population was obese?

It's possible (where was HIV in 1900?) but there's also heaps of excess food and door-to-door car service and couch potatoism behind most modern fatties. People who are trundled from meal to meal and who lie about like Roman emperors waiting to be entertained while they eat prepackaged bundles of salt, fat, and sugar are probably going to get fat regardless of this "infectobesity" stuff.
posted by pracowity at 1:26 PM on August 15, 2006 [1 favorite]