One of my favorite iPod apps is for Stitcher, which collects podcasts that I might be interested in listening to.  I must admit I favor either old time radio drama or history programing.  There’s nothing better to fall asleep to than the adventures of Captain Midnight or Fort Laramie. Stitcher’s “favorite playlist,” however, generates podcasts that everybody’s interested in, so I occasionally find myself listing to “This American Life” or “Fresh Air” from the NPR network.  It’s also where I’ve run across “Freakonomics,” associated with the University of Chicago’s Steven Levitt and New York Times journalist Stephen J. Dubner.  I did not know they were still talking since their best-selling 2005 book, but apparently they’ve never stopped. A recent podcast on Freakonomics took on obesity, especially obesity in children, in a sort of panel discussion format. It was interesting because the experts gathered were both what you might call ‘obesity insiders’ and those who were brought in for the one-time challenge of helping come up with a solution to the obesity problem.  Those brought in from the outside tended to focus on personal and parental responsibilities, while those who are involved year-round in obesity research or dealing with obesity populations tended to blame outside influences — like how some groceries are marketed to kids. The iPod discussion allowed all kinds of solutions to be put on the table, and  I heard everything from the use of certain tapeworms to ending the tax deductions for certain marketing expenses of food companies.  However, after hearing the spirited discussion, I was left feeling unfulfilled because the panel neither resolved anything nor did it get into the most promising solution for obesity that I truly believe is out there — finding a cure. We now know microbial flora in your intestine control your metabolism and body weight. The dominant of the single cell organisms, Methanobrevibacter smithii, is present in the intestinal tract of about 70 percent of people and its elevated in about 30 percent of those who are most likely genetically inclined to harbor higher levels of M. smithii. M. smithii harvests hydrogen molecules from surrounding microbes, making methane gas. We’ve known since 2004 that microscopic organisms living in our intestine have some control over whether we are obese or not. That pioneering research was the work of microbiologist Jeffrey Gordon and a team at Washington University School of Medicine in St. Louis. Then, last year, Zhao Liping, professor and dean at the School of Life Sciences and Biotechnology at Shanghai Jiao Tong University, presented research by his team showing how those microbes play a significant role in weight gain. The International Society for Microbial Ecology published Zhao’s research in peer-reviewed “ISME Journal.” Now Dr. Ruchi Mathur, director of diabetes, in the department of medicine at Cedars-Sinai Medical Center, has published a study in the Journal of Clinical Endocrinology & Metabolism, proving certain populations of microbes gives off a distinctive gas. Dr. Mathur says the research she and colleagues at Cedars-Sinai conducted is but “one piece in the complex puzzle that is obesity.” The “smell test” might help monitor the M. smithii activity in a person’s gut that is triggering weight gain. The possibility that some mix of microbes in our intestines controls our weight in a way that science does not yet fully understand should throw down a caution flag for all those wanting to use obesity as a political weapon. Obesity may not be the “gateway” condition leading to all those other problems like diabetes and the like. It might be at least a second step on a road of disease that starts in the gut. All of this is pretty exciting and obesity is not a subject for which there is much to get excited about.  We are all forced to listen to politicians who want to get as much out of the issue as they can, and every year Americans spend $60 billion in a desperate effort to change their diet and lose weight. These researchers, like Zhao, offer rare hope to the obese.  He was a relatively skinny Chinese kid when he attended Cornell University in New York.  By the time he returned to Shanghai, he was more than 60 pounds over weight.  But according to a profile I found on the Chinese professor written in German in the Berliner Zeitung, Zhao did not rely on just forsaking American fast food to return to a healthy weight. Instead, he sought out traditional recipes and relied upon a diet that largely consisted of yams to lose the weight and cut his blood lipid level.  He became convinced medicinal plants used in Chinese traditional medicine that was responsible for his weight loss.  That led to his interest in the relationship between gut flora and fat metabolism. So maybe the real solution to obesity lies both within ourselves and in science.

  • Katie Hill

    It’s important for readers to know that the japanese yam is different from the yams sold in our domestic food outlets, should some try to follow this method of losing weight!

    • SweetPotato Expert

      I’m wondering if it’s yams (like the true yam that is predominantly grown in Africa) or “yam” like what a lot of people call the sweetpotato. I’m betting it’s the sweetpotato and that it’s a Japanese variety. Regardless of variety, the sweetpotato is a “super food” and should be eaten often for weight control, though the purple (Asian varieties) and orange (typically seen in USA, South America, and Europe) sweetpotatoes are probably your best bet (though the white ones are awesome and tasty too!).

  • We look at this the wrong way.

    The best people for the future are those who need fewer calories. We don’t need to adjust the obese metabolism or gut flora–we need to adjust the eating habits of the obese. To learn to do with less.

    • Emily73

      Unfortunately, you’re wrong. A new study by NHANES found that the obese don’t consume more calories than thin people. It concludes, “Over the past 35 years in the USA when obesity has become increasingly prevalent, the intakes of energy and macronutrients among people of different BMI classes trended similarly over time. From these results, population trends in fat or carbohydrate intake do not clearly explain the rise in obesity prevalence.” Your attitude is part of the problem: blame the victim. Obesity is a complicated disease with many possible causes, including medication, viruses, substances in the food we eat, or different gut microflora.

      • The point is, if people need less calories for optimum weight, then this is actually an evolutionary advantage–not a disadvantage.

        This isn’t a ‘blame the victim’ issue at all–this is accepting that some people need less food than others. This is a good thing.

        What no one needs except on rare equations, regardless of weight, is a plethora of empty calories thinly disguised as ‘food’. I include in this most snack food, sweets, and especially soda. Over indulging of these items can lead to a host of problems including, but not specific, to obesity. Problems such as diabetes, heart trouble, and so on.

        The worst thing we can do is throw our hands up in the air, blame gut flora, demand a solution from science because we won’t accept our unique physical characteristics and tailor our consumption habits accordingly.

        • I wish I could easily edit without sending the comment back to limbo land…

          Make that “on rare occasions”, not equations.


      • Lynne Freezy

        I agree with you, Emily. I’m considered obese, even though accoding to my doctors, I’m quite healthy. My daily caloric intake averages 1200-1500 calories. I keep my fat calories to a minimum, eat whole grains, avoid white sugar/processed foods, and rarely eat restaurant foods. Yet, year after year, my weight stays the same. No hypertension, no diabetes or blood sugar problems, no sleep apnea, no difficulty breathing, etc. My weight issues stem more from the inability to exercise as much as I should (cervical spondylosis combined with degenerative disc disease). Knowing that, I keep my caloric intake down. I eat just as much (or as little) as my very thin sister. For me, it’s a battle, but not for her. Part genetics, part mechanics, I guess. Blaming the “victim” doesn’t solve the problem.

  • Lisa Malmar

    Again, we are looking for a ‘magic bullet’ when in comes to obesity. I believe that time will tell that it’s not just one thing and we have to look to our environment and the toxic soup we have created that is wreaking havoc on our endocrine systems and gut flora. Eating a yam isn’t going to do it for most of us. We’d also do a better to stop stigmatizing weight and looking at the real facts – many people who are overweight are not sick – we only focus on the sick – then see weight as the disease instead of inactivity, the kinds of foods we eat and so on.

  • Kathleen Silloway

    Has there been any work done on whether there is a correlation between the exuberant presence of these microbes in some people and what they consume?