Saturday, December 22, 2012

The Nutrition Debate #80: Obesity Caused by Gut Bacterium!

A few days ago, the Health page of the Financial Times online ( here) led with the banner headline, “Scientists Link Obesity to Gut Bacteria.”Call me a skeptic, if you like, or even a “conventional thinker” (pulleesse, don’t call me that!), but I’ll have to “wait and see” on this one. I know, a lot of serious scientists have been talking and writing about this in the blogosphere lately, but this is the first that I have seen it in the “mainstream” media.

So far, I have been dismissing this talk as too “edgy” and too esoteric for my non-scientific brain to wrap around. Besides, I have just gotten comfortable with – in fact, fully embraced Gary Taubes’s alternative Carbohydrate Hypothesis. This theorem places the action – or rather the “broken” action, of the hormone insulin at the center of the obesity epidemic. And now some cutting edge thinkers are moving on to another frontier – the human gut.

I suppose it’s a good thing that science is “advancing” quickly, but scientists would be the first to say that caution is and should be the “order of the day.” And I have no doubt it will. Everything will be “peer reviewed” (for what that’s worth!), and replicated with double-blind, prospective, trials, etc, etc. But journalism is not so constrained, and journalists often get it wrong. And, as a result, so does the public. And then the processed and packaged food industries pick-up on it, and all of a sudden a box of Cheerios cereal is a cholesterol-lowering drug.

But this rant is not about the gut bacterium “discovered” by the Chinese scientists at Shanghai Jiao Tong University, as reported by Professor Zhao Liping in the FT.  It is about the response of Dr. David Weinkove, lecturer in biological sciences at Durham University in Durham, England. Durham, for my non-British readers, is listed third after Oxford and Cambridge in many rankings of institutions of higher learning in the UK. I gave a hearty guffaw when I read his reaction to the news. He said, according to the FT, “If obesity is caused by bacteria, it could be infectious and picked up from some unknown environmental factor, or a parent. IT MIGHT NOT BE BEHAVIORAL AT ALL” (emphasis mine).

I apologize for “shouting” but I just couldn’t believe that he said this. I accept that the vast majority of the lay public believes that nearly 50% of all the adults in the U.S. and the UK are obese because we eat too much and exercise too little. But, for a lecturer in biological science at a leading UK center of research and learning to say it?!! Give me a break!

In an email exchange I had with Gary Taubes on the day before I wrote this, he related to me that he was preparing a rebuttal to the British Medical Journal (BMJ) on a piece they had just published about how low fat diets were associated with weight loss. I read the piece and decided that it was beyond my ken. I replied to him that I would leave the BMJ to him, and I would continue to fight “the good fight” on a different level. But when I am reminded how far we (all of us with an open-minded view of the science) have to “climb” to overcome such ignorance, it is indeed a daunting prospect.

Anyway, if the “gut bacteria” news had escaped your notice by the time this post hits the blogosphere, let me bring you up to speed. Dr. Zhao, the lead scientist and spokesman for the study, asserted, “This is a very important phenomenon. It is the last missing piece of evidence (that) bacteria causes (sic) obesity.” I laughed again at this as I could imagine Dr. Weinkove (of Durham) salivating at the prospect of what that breakthrough news portends. I saw a vision of sugar plums dancing in his head when he said, as the FT reported, “Dr. Zhao’s research paved the way to intervene in obesity and could allow new drugs to be developed for treatment.” It reminded me of the researchers and drug developers who first  came up with the statin compounds to lower LDL lipoproteins, and thus Total Cholesterol (TC,) because LDL was the only sub-component of TC that they could easily and effectively lower with a drug. This led to world-wide sales today of well over $20 billion, and to dubious health benefits and myriad risks. But it was a boon to the bottom line of big pharma.  Billions in profits and decades of grants for the “research community” ensued, both in academia and industry.

So, while I am skeptical by nature, and that is a good thing both in science and in general, I am still open-minded. I can also hope that this is “a very important phenomenon” and that it is “the last missing piece of evidence” of what causes obesity. And just as cholesterol testing was developed in the 1980s and then evolved beyond LDL, let’s hope that gut bacteria research, whether relevant to obesity of not, evolves as well. After all, as everyone is fond of saying, “there are 10 times more microbes than human cells in our bodies and they can be beneficial.” So, as science advances, particularly with recent progress in the knowledge of the human genome, a “breakthrough” of this magnitude would be welcome. Semi-starvation on a “balanced” diet, and boring daily exercises, don’t work for most people. And my VLC Ketogenic Diet is certainly restrictive and requires discipline. And I like my sugar plums…and Christmas cookies too!
© Dan Brown 12/22/12


  1. If gut bacteria could cause obesity, I would surmise it still goes back to overeating carbohydrates. Perhaps they stimulate the growth of bad bacteria, or cause good bacteria to behave badly. But there are so many people who have been over prescribed antibiotics that kill gut bacteria, I wonder that anyone has any left. Maybe it's the lack of gut bacteria that causes obesity? Buy stock in probiotics.

    1. Right! Good one. I took a probiotic on the advice of an emergency room doc last year after I had been prescribed an anitbiotic by him. The probiotic gave me gas, but I thought it was enlightened of the doc to tell me to take it to help restore my gut bacteria.

      Anyway, there is increased interest in gut bacteria I think because we can know more about them in large part to the work on the human biome made possible by the DNA breakthroughs. My editor and her husbans are going to have their gut bacteria analyzed American Gut. Google it. For $99 dollarw/person, you can learn a lot. Another similar $99 program is "twenty three and me," referring to the number of chromosomes we have. American Gut will use stool or other samples; 23+me uses saliva samples. Both sound interesting to me, but I'm still thinking about it for myself.