Can You Smell Obesity?

According to the latest research, it may be on your breath.

  • Share
  • Read Later
Getty Images / Getty Images

According to the latest research, it may be on your breath.

It turns out that obesity may be detectable as a gas, thanks to organisms that inhabit our gut. In a study published in the Journal of Clinical Endocrinology & Metabolism, researchers extend our knowledge about the hidden universe of the microbes that live within us to show that obesity is associated with certain populations of microbes that give off a distinctive gas.

To be more specific, obesity may smell a lot like…methane, which is to say, like not much at all, since methane in its naturally-occurring state is actually odorless. In the study. Dr. Ruchi Mathur, director of diabetes in the department of medicine at Cedars-Sinai Medical Center, and her colleagues analyzed the breath of 792 men and women of various ages. Mathur focused on detecting methane in the breath, since animal studies found that the presence of a certain family of organisms called archaea, which are older than bacteria and colonize the gut, was linked with weight gain and conveniently released small amounts of methane gas. Mathur also knew from her own work analyzing the gas makeup of the breath from bariatric surgery patients that those releasing higher levels of methane in their breath tended to have a body mass index (BMI) nearly 7 points higher on average than those with lower levels.

(MORE: The Good Bugs: How the Germs in Your Body Keep You Healthy)

And sure enough, Mathur found that among the nearly 800 participants she tested, those with higher levels of methane (3 or more parts per million over 90 minutes) and hydrogen gases (20 or more parts per million) in their breath also tended to be heavier, with a BMI about 2.4 points greater than those with normal levels of the gases and about six percent more body fat on average.

“Our hope is that this is one piece of the complex puzzle that is obesity,” says Mathur, “and that by identifying people who are obese because they have this microorganism, we can manipulate and work with the gut microbiome to lead to benefits in weight loss in that subgroup.”

(MORE: What Do Gut Bugs Have to Do With High Cholesterol? A Lot)

The culprit, she believes, is a member of archaea known as Methanobrevibacter smithii, which is present in the intestinal tract of about 70% of people, but elevated in about 30%. It’s that smaller group of individuals who might be genetically predisposed to harboring levels of M. smithii that might put them at higher risk of developing obesity. M. smithii harvests hydrogen molecules from neighboring microbes in the gut, which it then transforms into methane gas. The more it scavenges hydrogen from its environment, the more other microbes produce. But all of that activity is focused on extracting energy and nutrients from food, so along with the hydrogen gas, the microbes are also packing in more calories for the host, which can lead to weight gain. It’s also possible, says Mathur, that the release of methane slows the transit of digested food through the intestinal tract, and that could increase the time for additional calories from digested food to be absorbed and added to the body’s tally.

In order for M. smithii to thrive, it needs the hydrogen from surrounding microbes, and that may be why people with higher levels of both hydrogen and methane gases in their breath were heavier than those with elevated levels of methane or hydrogen alone.

(MORE: Skim Milk May Not Lower Obesity Risk Among Children)

So how does this help control the obesity epidemic? For those whose weight gain may be due in part to the activity of M. smithii, controlling the organisms with antibiotics or other medications could slow down the rate at which they pack on the pounds, and these individuals could easily be identified with a relatively simple breath test.

Mathur and her colleagues are also working with the American Diabetes Association to test a group of people with prediabetes who are overweight or obese and have elevated levels of methane in their breath. The researchers will test the participants’ glucose tolerance, the time it takes for digested food to transit through the intestinal tract, and the amount of calories in the patients’ stool. Then they volunteers will be given an antibiotic to essentially wipe out the population of M. smithii and the same parameters will be measured again, to see if eliminating the microbes will help change the patient’s weight profile and alter their trajectory toward diabetes.

She is also studying a group of children to see how early M. smithii buildup occurs, and how soon in development it starts to set up a pattern of weight gain that might then be interrupted by changing the composition of the gut microbial world. “From an evolutionary perspective, our relationship with the microorganisms that live in us has basically been symbiotic, and we have evolved together,” she says. “We’ve had that relationship for millenia, but it is just now being explored and discovered in more detail.” And, when it comes to controlling the obesity epidemic, could lead to the (sweet?) smell of success.

MORE: Americans Are Eating Fewer Calories, So Why Are We Still Obese?

74 comments
prittypixy
prittypixy

Just look m. smithii up on Wikipedia and you will read that "the quantification average of M. smithii for the anorexic group was much greater than the lean and obese group. Thus, higher amounts of M. smithii were found in anorexic patients than lean patients."  So, obviously killing m. smithii off in fat people will accomplish nothing since they already have lower quantities. M. smithii increase in number when food becomes more scarce. Since the numbers of m. smithii were shown to be less in obese people already than it seems fairly pointless to forcefully kill the archaea  off with antibiotics. In truth the thought of killing off symbiotic archaea that has worked with our bodies for thousands of years seems short-sighted and fool hardy.

pfschafer5
pfschafer5

Isn't it far more likely that obesity (or the habits that make someone obese) cause the increase in M. smithii, and not the other way around. Shame on the author for not addressing that. Time knows its better to sell the obesity cure, than to do actual reporting.

LizMani
LizMani

@TIME really? Hmn hmn!!! You can Smell Fat??? LMao! Funny

OtherTuscaloosa
OtherTuscaloosa

Obesity could be treated with antibiotics? Now there's a great idea. Not at all.

Albacorewing
Albacorewing

Well, over the years we have heard that obese people cause global warming, use too much in the way of resources, and NOW we can smell them.

When will the death camps and ovens be ready?

thewholetruth
thewholetruth

HOW TO LOSE WEIGHT:  An Insulin resistance Diet works  to  drop weight naturally, if you are diabetic or NOT  an insulin resistance diet naturally drops fat. We are all insulin resistant today due to food chemicals, this is why dieting fails.  A insulin resistance diet reverses the damage from food chemicals and the weight drops off, this worked in 10 countries 

 SEE Here http://type2diabetesdietplan.blogspot.com/2013/02/what-should-diabetic-eat.html



samaraluck
samaraluck

%s %s Wow, that spurned a lot of 'schoolyard' fat jokes!! Your ego wants you to believe obesity is a moral issue %s

rajeev2liz
rajeev2liz

%s %s the %s %s has always been a problem due to all the fast food joints and lack of exercise

BatMondo
BatMondo

@TIME I'm pretty sure I don't need to smell fat people to tell they're fat

BigVelociraptor
BigVelociraptor

@TIME No, but I can smell a fresh bucket of KFC, that's pretty much the same thing, right?

IgnatiusAryono
IgnatiusAryono

@AriWahyunanto yang ku RT dari TIME tadi artikel ttg riset yang mengatakan bahwa diabetes dpt dideteksi dari unsur yg ada di nafas seseorg