Hobby Lobby and me

Okay, no real connection.  Though I do get a big kick out of the fact that the president is Steve Green (the spelling of my name used by lazy students who annoy me– is the damn “e” at the end so hard?).  Anyway, the other Steve Green wants to build a bible museum in the heart of our nation’s capital.  Why?  Apparently he doesn’t actually understand American history:

The Bible museum’s proximity to the seat of U.S. government is no accident.

“As many people as we can educate about this book, the better,” Green said. “I think seeing the biblical foundations of our nation — for our legislators to see that, that a lot of that was biblically based, that we have religious freedoms today, which are a biblical concept, it can’t hurt being there.”

Riiiight.  The biblical foundations of the US Constitution.  And even freedom of religion.  Either Green has been reading the wrong bible or the wrong Constitution.

Is Nutrasweet ruining my microbiome?

I suspect not (though still waiting on the American Gut project to send me the results of my very own intestinal microbiome), but some very interesting new evidence brings together research on two of my favorite topics– the human microbiome and artificial sweeteners.  I was not entirely sold by the WP write-up of the research, but this NYT story really gets into the details of the methodology and there’s surely something going on here:

In the initial set of experiments, the scientists added saccharin (the sweetener in the pink packets of Sweet’N Low), sucralose (the yellow packets of Splenda) or aspartame (the blue packets of Equal) to the drinking water of 10-week-old mice. Other mice drank plain water or water supplemented with glucose or with ordinary table sugar. After a week, there was little change in the mice who drank water or sugar water, but the group getting artificial sweeteners developed marked intolerance to glucose.

Glucose intolerance, in which the body is less able to cope with large amounts of sugar, can lead to more serious illnesses like metabolic syndrome and Type 2 diabetes.

When the researchers treated the mice with antibiotics, killing much of the bacteria in the digestive system, the glucose intolerance went away…

To further test their hypothesis that the change in glucose metabolism was caused by a change in bacteria, they performed another series of experiments, this time focusing just on saccharin. They took intestinal bacteria from mice who had drank saccharin-laced water and injected them in mice that had never been exposed any saccharin. Those mice developed the same glucose intolerance. And DNA sequencing showed that saccharin had markedly changed the variety of bacteria in the guts of the mice that consumed it.

Honestly, that’s pretty compelling stuff.  And as much as my motivated reasoning wants to knock it all down, it is clear that there is something going on.  One of the researchers changed his own habits:

While acknowledging that it is too early for broad or definitive conclusions, Dr. Elinav said he had already changed his own behavior.

“I’ve consumed very large amounts of coffee, and extensively used sweeteners, thinking like many other people that they are at least not harmful to me and perhaps even beneficial,” he said. “Given the surprising results that we got in our study, I made a personal preference to stop using them.

As for me, I’m definitely going to keep following this research, but I’m not yet ready to give up my diet sodas.  This is a laboratory experiment with mice. The factors influencing the human microbiome awash in artificial sweeteners, and sugar, and the myriad other features of life, food and otherwise, that surely affect our microbiome have got to be quite complex.  My naive hypothesis would be that for some humans with some lifestyles artificial sweeteners are a bad thing.  Perhaps even worse than excess sugar.  For now, though, I’m willing to gamble that, at least for me personally, between lots of fruits and vegetables, whole grains, and plenty of exercise, (and probiotics via yogurt and Culturelle), that my microbiome is still looking pretty good.

Now, as for society, I think the evidence is pretty compelling that you should avoid sweetened drinks if at all possible.  That said, if you are drinking soda (surely the main source of artificial sweeteners) the jury is still very much out on whether regular or diet is likely to cause you more harm.

Smells liberal

A friend last week sent around a link to the new article nicely summarized here which prompted much joking on the matter:

A new study from the American Journal of Political Scienceindicates that different political affiliations may actually correspond with different body odors.

The researchers, led by Brown University political scientist Rose McDermott, found that conservatives and liberals smell dissimilar. While the difference is small, it is apparently significant enough that we subconsciously prefer the scent of those who vote like we do. “It appears nature stacks the deck to make politically similar partners more attractive to each other in unconscious ways,” the researchers wrote.

The how is here.  It’s not quite fair to say that someone smells conservative or liberal.  More so, like attracts like:

They got 146 participants to rate the attractiveness of the body odor of unknown strong liberals and strong conservatives, without ever seeing the individuals whose smells they were evaluating. Based on that, they concluded that people find the smell of others with similar political opinions to be attractive, suggesting that one of the reasons why so many spouses share similar political views is because they were initially and subconsciously attracted to each other’s body odor.

“People could not predict the political ideology of others by smell if you asked them, but they differentially found the smell of those who aligned with them more attractive. So I believe smell conveys important information about long-term affinity in political ideology that becomes incorporated into a key component of subconscious attraction,” said Dr. Rose McDermott, lead author of the paper.

I actually looked through the original article and I’m going to have throw some cold water on this.  The support for the hypothesis touted far and wide (lots of links to this story– okay, including me) was significant at p<.1, one-tailed.

In both models, we observe the hypothesized positive coefficient on the negative absolute difference in ideology scores (–Abs. Ideology Diff.), though in both cases the coefficient is less precisely estimated (t = 1.48 in Model 1 and t = 1.45 in Model 2), but still with one-sided p-values less than 0.1. In all cases, the substantive effect of ideological similarity is small, which is to be expected.

How in the world such marginal results got published in the 2nd most prestigious journal is beyond me.  Peer review is supposed to be blind, but I strongly suspect that having prestigious scholars behind the research had something to do with it.  “the coefficient is less precisely estimated”!?  I’m going to have to try that next time I don’t get the statistical significance I want.

Honestly, if the best result I got was p<.1, one-tailed on my key hypothesis, I don’t think I’d send to any journal.  And if I only had 146 subjects, the first thing I would do is get more to increase the statistical power in hopes of having more compelling statistical significance.  Anyway, this is also a great example of how the seal of approval from a major peer-reviewed journal means lots of wide-spread attention when the group of 7 political scientists I discussed this with last week over lunch who had seen the actual article were all skeptical.  At least makes for some good political humor.