Assorted links

by on March 30, 2012 at 2:03 pm in Uncategorized | Permalink

1. Moral hazard in Austria.

2. Joe Peta’s statistical analyses of baseball teams.

3. Now on-line, the complete Libertarian Review.

4. Are moderates losing trust in science?

5. Canada to abolish the penny.

Andrew' March 30, 2012 at 2:11 pm

4. Funny how they frame it, right?

JWatts March 30, 2012 at 7:10 pm

Yes, you can look at that chart and say “Conservative and moderates opinion about Science has converged”, but the author who is self admittedly left leaning chose to essentially ignore that aspect and frame it as a conservative/liberal issue.

Obviously Tyler caught that too.

The Original D March 30, 2012 at 11:09 pm

After 1982 moderates more or less go sideways, so you can’t say they’re “losing” trust. Conservatives are steadily going down.

JWatts March 30, 2012 at 11:19 pm

“After 1982 moderates more or less go sideways, so you can’t say they’re “losing” trust.” Well since I didn’t say that, your comment seems odd.

Andrew' March 31, 2012 at 8:09 am

I do give the researcher credit. Despite being liberal he came off as about even-handed as one could hope.

Andrew' March 31, 2012 at 8:10 am

On the other hand, it’s obvious that when they frame things like this (also, why has liberal confidence in science institutions increased?), shouldn’t conservatives be distrustful?

Alan March 30, 2012 at 2:41 pm

#4

Do you trust your cell phone to make calls? Yes. Do you trust Maxwell’s equations? Huh?

Do you trust your GPS to find an address? Yes. Do you trust relativistic time dilation? Huh?

Michael March 30, 2012 at 4:43 pm

If you go all the way through to the actual question asked in the GSS, it was not about trust in “science”, but trust in leaders of scientific institutions. Quite rightly, basically all news reports floating around this report recently should be taken with a huge grain of salt, as Tyler apparently did.

Amusingly, this entire news story is basically a self-fulfilling meme. A Ph.D. Sociologist basically calling conservatives “idiots” when they’re highly educated is a great way to endear them to the cause of “science”.

Jeff March 30, 2012 at 5:34 pm

+1. Kevin at least kept of the appearance of trying to think through these issues in the past, but yes, he and others are gleefully reporting “science” not “scientific institutions.”

Benny Lava March 30, 2012 at 7:05 pm

Well aren’t they?

tkehler March 30, 2012 at 9:26 pm

Did you read the piece? The point wasn’t about tacit or pragmatic knowledge (like trusting a cell phone to work). It was that there is now widespread skepticism about the organs that disseminate knowledge — universities etc. — and this skepticism is driven by people who are by and large well educated.

Let me ask you this: do you trust the writings of contemporary film theorists, even those teaching at Ivy League universities? I no longer do. I trust the Roger Eberts / Susan Sontags / Pauline Kaels / Anthony Lanes of the world, in part because film theorists are talking too busy writing gibberish about the phallologocentric gaze of the transgressive signifier, to tell me about the film I’m interested in seeing.

tkehler March 30, 2012 at 9:29 pm

Okay so I moved from discussing science to discussing academe’s privileged knowledge (in film studies), but I’m not that far off. After all, the impulse behind the particular (and impenetrable) jargon proffered by far-out film theorists is scientism.

Beefcake the Mighty March 30, 2012 at 9:32 pm

Not sure what you’re getting at, but anyway: fuck off.

tkehler March 30, 2012 at 9:53 pm

Yes, you are right. You aren’t sure what I’m getting at.

The Original D March 30, 2012 at 11:12 pm

I trust that researchers at MIT, Stanford and, yes, even Berkeley are doing really hard work to help us better understand the universe. I bet Roger Ebert and Anthony Lane do too.

derek March 30, 2012 at 11:05 pm

I hope you are not suggesting that the mathematical predictability that characterizes much of physics applies to other sciences such as economics, medical, or social sciences.

If so you are either 1) ignorant, or 2) untrustworthy as a source of scientific knowledge and understanding.

tkehler March 30, 2012 at 11:57 pm

I agree with you about the hard sciences, like physics (and I don’t even have physics envy).

However, my take on the whole controversy is that there’s been a decline in trust in knowledge, not just science (however you define it). If we grant this, we can see that the hard sciences, incl. physics, have been swept along in the wake of this decline. Clearly some of this is attributable to the increased mistrust of the academe.

Bill N March 30, 2012 at 2:47 pm

#4, Typical Kevin Drum blather. He should read “Norms and Counter-Norms in a Select Group of the Apollo Moon Scientists: A Case Study of the Ambivalence of Scientists” ( sorry but it is gated http://www.jstor.org/stable/2094423 ) but I don’t think he’d understand it.

There is a difference between not trusting science and acknowledging that scientists are human and the process is messy so we should take our time and let it play out.

On second thought, the press is probably more to blame, as they regularly exaggerate or misrepresent science reports.

dearieme March 30, 2012 at 2:48 pm

I have lost faith not in science, but in some of the junk passed off as science.

Of course I believe in Evolution, in the Physics of Newton, Clerk Maxwell, Planck and Einstein, and lots of other well-founded stuff. But am I really expect me to rush about singing the praises of string theory? Climate science? The masses of epidemiological correlative studies passed off as medical science? Or the fantasies and untruths that so often accompany the useful truths about nutrition? Am I really expected to take seriously all those scientists whose every public pronouncement translates as “Give me da money”?

Aneesh March 30, 2012 at 3:07 pm

Am I really expected to take seriously all those scientists whose every public pronouncement translates as “Give me da money”?

Why is conservative faith in “give me da money” preachers and churches still strong, and apparently getting stronger?

msgkings March 30, 2012 at 6:04 pm

Why are you asking a mostly atheistic bunch of libertarians here?

Josh March 31, 2012 at 2:20 am

I think it’s because you know what you are getting with churches; hopefully (if you go to a decent church) you get a nifty sing along, uplifting lecture that amounts to “don’t be a jerk” and eternal salvation. Give money to science, and who knows what you end up with. Maybe you get new technology, transformative innovation or perhaps nothing at all. Actually, now that I’ve typed it out, the two don’t seem to have much in common, do they?

JonF311 March 31, 2012 at 11:42 am

Re: I think it’s because you know what you are getting with churches

The claims made by religious bodies are untestable in this life. So no, you do not know what you getting.

J March 31, 2012 at 3:44 pm

The two aren’t analogous. Giving money to a church is voluntary, funding government grants, however beneficial they may or may not be, isn’t. Also, churches do a lot of things in addition to those mentioned, such as anti-poverty work. And because of their financial structure, they have no incentive to perpetuate poverty or other ills, unlike their public sector competitors.

In any case, I don’t know why we’re arguing about this. The claim that the study measures confidence in science has already been debunked; it doesn’t.

The Original D March 30, 2012 at 11:14 pm

Ah yes, it’s those scientists who are bleeding us dry. Especially compared to, say, the military or old people.

Andrew' March 31, 2012 at 8:11 am

Ah yes, revealed preferences of the left.

dead serious March 31, 2012 at 12:00 pm

Magnitude does matter.

J March 31, 2012 at 3:52 pm

The military buys a lot of scientific research. About $78B in FY 2012.

Floccina March 30, 2012 at 2:49 pm

#4 what science?
The other day I heard that some big Harvard scientific study showed the eating red meat shortens lives. I did not trust it.

Now on the right left divide on science, I remember my college plant pathology professor speaking of pesticides, saying if it oxidizes in 24 hours, it is gone in 24 hours and it is safe to eat. But it is not mostly conservatives that pay more for organic food. The left on GM food etc. could be considered a rejection of science too and their are other examples.

Leftist do not trust some science and rightists do not trust some other science which has more negative real effects, I do not know.

Andrew' March 30, 2012 at 3:19 pm

In one story about the study, this was the case in Europe where the left concerned more with GMOs don’t trust science.

Here’s the cheat sheet:

US: science + government = conservative distrust
Europe: science + industry = liberal distrust

Tony March 30, 2012 at 4:14 pm

science + industry garners a fair amount of liberal distrust on this side of the pond as well. (Ok, anything + industry does.)

dead serious March 31, 2012 at 12:02 pm

As does anything “+ government” garner right-wing distrust.

john personna March 30, 2012 at 4:29 pm

The meat study was not terrible, but was mis-reported. It becomes a case-study in science and science-reportage. (The ‘problem’ with the study was that it did not differentiate between processed or preserved meats and the fresh stuff.)

Andrew' March 30, 2012 at 4:44 pm

Yes. My first question was about nitrites. At the very least, you can’t trust them to run good studies.

And its funny, if you are among a bunch of scientists discussing scientists, you talk about how bad their study design is. If you talk about non-scientists you wonder why they don’t trust scientists.

john personna March 30, 2012 at 5:41 pm

Well yeah, but we should teach journalists and lay people to have enough patience to read that far. I mean, I know people who probably do eat the tested mix of processed and unprocessed meats. For them it is good data. It’s just not good data for the subset already restricting types of meat consumed.

Michael March 30, 2012 at 5:01 pm

Hear, hear. Sadly, the majority of the “environmental” movement is little more than a bunch of neo-luddities who fetishize anything “natural”. Well, guess what, hemlock is natural too, ya know? But I ain’t gonna drink it.

Between distrust of GM food, or Nuclear power, and that gawd awful Erin Brockovich, to organic food, or the idiotic belief that electric cars are “zero emission”, there is just as much scientific ignorance and probably more overt hostility on elements of the left as on elements of the right.

Andrew' March 31, 2012 at 8:14 am

As I’ve said before I almost entirely lack the joiner gene. So, I like the Environmental Working Group’s assessment of “the dirty dozen” and healthy fish (with a wink to sustainability) completely ignore most of the rest. In fact, things that are okay to buy conventional generally require less pesticides and thus are more sustainable and healthier and cheaper because we aren’t trying to grow them where they shouldn’t be grown. But if you have the joiner gene you are likely to treat something like environmentalism like a church.

J March 31, 2012 at 4:03 pm

Organic food is a vanity product for relatively wealthy consumers. The average conservative is wealthier than the average liberal, and thus better able to afford and more likely to buy such things.

cb March 30, 2012 at 2:50 pm

Are moderates losing trust in science? Based on that chart? Huh?

1. They are in an upward trend since 2002, with 2004 higher than 2002, 2006 higher than 2004, and 2008 higher than 2006.

2. Moderates are essentially at their long run average of ~0.4. The only significant decline in trust for them occurred in the 1970s.

3. Meanwhile, conservatives have dropped consistently from about 0.5 to about 0.37 over the time period.

Andrew' March 30, 2012 at 3:26 pm

It depends on what your definition of “are” be.

JWatts March 30, 2012 at 7:25 pm

“2. Moderates are essentially at their long run average of ~0.4. The only significant decline in trust for them occurred in the 1970s.

3. Meanwhile, conservatives have dropped consistently from about 0.5 to about 0.37 over the time period.”

So, Moderates and Conservatives opinion of science has converged, while liberals remain outliers.

The Original D March 30, 2012 at 11:17 pm

Other way around. Liberal trust has remained at roughly the same level. Conservatives have changed relative to the historic norm.

JWatts March 30, 2012 at 11:31 pm

“Other way around.”

If you insist: Liberals are outliers, while moderate and conservative opinions of science has converged. Yep, your right, it works better that way.

Difference between Conservative and Moderates in 1975, about 0.4. Difference between Conservatives and Moderates in 2008, about 0.2. See they are closer together. That would be convergence. Meanwhile, the 2008 difference between Conservative/Moderates and Liberals is about 1.0. So Liberals are outliers.

FYI March 30, 2012 at 2:59 pm

I’d say #4 is a clear reaction to the global warming debate where a lot of politics was disguised as science. For instance, I believe the planet is warming and I also believe human activity is at least part of the cause. However, to assume that because of that we have no other option than to curb economic activity at all costs is absurd, no matter what scientists say. This kind of economic policy question is much, much larger than science.

So if you ask me if I “believe in global warming” I might say no because a huge number of assumptions are embeeded into that statement.

Zachary March 31, 2012 at 1:15 am

Good comment. It is important to recognize the positions that both characterize the ‘conservative’ field and those that are taken by mainstream science. If mainstream science means to infer certain policies are appropriate, then it is not really science but is a piece of policy opinion. Real Science reveals information about the world around us and merely presents us with the reality for us to value in terms of our own preferences.

A Berman March 30, 2012 at 3:41 pm

We haven’t lost faith in science.
We’ve lost faith in scientists.

NAME REDACTED March 30, 2012 at 6:47 pm

+1

Daniel Dostal March 30, 2012 at 8:27 pm

We had too much faith in scientists and not enough in the scientific method backing those scientists. Way too much appeal to authority for laymen.

tkehler March 30, 2012 at 9:32 pm

The New Left of the ’60s politicized science. This didn’t bother liberals that much, though many of the Old Left were aghast. But it bothered moderates and conservatives.

JonF311 March 31, 2012 at 11:44 am

In what way did the New Left politicize science? Genuinely curious where you see that.

tkehler March 31, 2012 at 8:52 pm

Gross’s book, Higher Superstition is good on this topic. But also the controversy surrounding the Sokal hoax, to see how the newer New Left went even further than the New Left.

Michael Cain March 30, 2012 at 11:17 pm

And following the recent financial fiasco, macroeconomists in particular.

Ted Craig March 30, 2012 at 4:26 pm

2. Some of Pena’s observations are kind of shallow for a guy that purports to offer numerical insight others ignore.

Ken Rhodes March 30, 2012 at 9:23 pm

Right — I’d characterize Pena’s approach as “Stratomatic stats.”

In that game, plays were reduced to random outcomes determined by dice. Modern Sabermetrics has advanced FAR beyond that in discovering interrelationships among stats, as well as predictions of outcomes based on performance stats far more complex than dice. Pena is not a Sabermetrics kind of writer.

Floccina March 30, 2012 at 4:29 pm

#5 very sensible. When can we drop the penny in the USA?

CMS March 30, 2012 at 4:32 pm

“Round metal dirt” a friend of mine once commented.

Andrew' March 30, 2012 at 4:45 pm

Have sales taxes round up to the nearest nickel?

JWatts March 30, 2012 at 7:26 pm

Well I’d prefer having taxes just round to the nearest nickel, not round up, but it’s not a big deal either way.

The Original D March 30, 2012 at 11:19 pm

The Fed probably prefers rounding up. :)

Steko March 30, 2012 at 11:40 pm

Generally if shops collect more from customers for sales tax than their liability to the government (e.g. by rounding up every time) they aren’t allowed to keep the difference. Since their tax liability is figured in aggregate it’s generally easiest to round to the nearest and not up.

Zachary March 31, 2012 at 1:22 am

There is a little Chinese restaurant in Jefferson mall of Louisville, KY that gives change, of the lowest terms, in nickles. They round up their change. If you are owed pennies, then they give you a nickle. They are very popular, they save time, and they build customer good will by changing slightly more than is correct. If the penny is not really valued by customers, then businesses will compete on it. I see no reason to further involve the government in monetary policy.

dead serious March 31, 2012 at 12:10 pm

Can we also get rid of the nickel?

The Other Jim March 31, 2012 at 7:02 pm

Go to youtube and search on “Death to Pennies.” The video will explain how the penny AND nickel are long past useless. The dime is getting there.

It’s embarrassing that Canada took action on this before we did. Although I admit it’s adorable when they pretend to be another country.

bellisaurius March 30, 2012 at 5:21 pm

I wish they split up exactly which branches they were talking about. We might find some interesting trends. I’m sure there’d be fairly decent agreement amongst the major sciences Physics, and chemistry.

Biology might have some agreement, but I’d bet there’d be a split between pharmacology and nutrition for liberals and conservatives. I’ve seen too many poorly reported stories on the nutrition topic to trust a lot of what I hear, I’d imagine a lot of liberals think there could be tougher reporting for pharmacology.

Meteorology generally, in the sense of storm warnings and such would probably get rough agreement, but climate studies wouldn’t (again, I blame reporting. If the press could be a bit tougher when they report the latest study, it’d probably be better).

If they included engineering in the sciences, I bet there’d be a much better conservative opinion of science, and possibly a somewhat lower one with liberals. Environmental sciences would swing the other way, a shame because there’s useful hydrology studies and such.

If one were to include the softer sciences, I bet we would see a good split between economics and sociology. I’m not entirely certain where anthropology and archaeology would fall, though.

So, overall we obviously have woldview cherry picking (I do it too,of course). I personally think it’s a media issue since they’ve become a center of the culture wars (blame who you will for that), but it’s a shame to see legitimacy lost amongst a group that I think actually does a good job within the limitations of being a human being, with all the biases that entails.

albert magnus March 30, 2012 at 7:03 pm

Until we can do experiments on humans in controlled situations like we do rats, medicine, nutrition, psychology and every other human oriented science will always be inferior to the non-human oriented sciences. The more you can isolate the effect you are trying to measure the more useful the results.

BrentR March 30, 2012 at 9:27 pm

On #4, It is kind of ironic that this case illustrates part of the problem.

There is a survey that is given every year that asks questions about trust in institutions, including “the scientific community.” Here is the description in the study about the types of questions in the survey:

The GSS asked respondents the following question: “I am going to name some institutions in this country. As far as the people running these institutions are concerned, would you say you have a great deal of confidence, only some confidence, or hardly any confidence at all in them [the Scientific Community]?” Respondents were then given the choice to respond “a great deal,” “only some,” or “hardly any” (they could also choose “don’t know” or “refuse”).

The study does some analysis, slicing and dicing data about answers to these types of questions over time, and finds that “To summarize the main empirical findings,
this study shows that public trust in science has not declined since the 1970s except among conservatives and those who frequently attend church.”

And then the news reports that conservatives hate science.

The actual data in the report is pretty interesting, but the way it is presented in the report, and reported by the news, is slanted to the point of being untrustworthy.

It took me about 15 extra minutes of my time to digest what was really going on. It is much easier just to dismiss everything you read on the news about scientific studies as shoddy reporting of an experiment that might or might not have been well constructed.

Me, Myself and AI March 30, 2012 at 9:28 pm

Looks like conservative trust in science took a dive right after the revocation of the Fairness Doctrine and the consequent rise of conservative talk radio.

tkehler March 30, 2012 at 9:57 pm

But there’s a distinct liberal dive too, around the late seventies. In fact, all three took a dive. To what can we attribute that?

The Original D March 30, 2012 at 11:22 pm

Stagflation, high gas prices, the Iranian hostage crisis, no major NASA launches, Carter’s “malaise”, etc

ben March 30, 2012 at 10:16 pm

Just wanted to say, for people who know both baseball and statistics well, Joe Peta’s analysis is very low level. His “predictions” are pretty clearly just hunches, with weak ex post justifications that do not in any way reflect an objective analysis of the data. This is totally fine for some guy who just wants to blog about what he thinks about baseball, but it’s really not up to the standards of MR at all.

Benny Lava March 30, 2012 at 10:32 pm

4. No surprise. Just peruse your favorite conservatives regarding knowledge:

http://www.conservapedia.com/Main_Page

http://usconservatives.about.com/od/education/i/CreateOrEvolve.htm

http://www.theconservativereview.com/tag/creationism/

Conservatives are anti-science because science disproves their worldview. As America becomes more polarized and ideological, conservatism and creationism and other such things are ever more closely intertwined. Moderates are becoming more conservative, hence rejecting science, that pesky thing.

Andrew' March 31, 2012 at 8:19 am

You are almost right…

Conservatives are anti (government-associated) scientists because LIBERALS THINK THEIR VIEW OF SCIENCE disproves conservative worldview.

Also, a lot of science happens completely outside of government. I did some. Now I’m still outside of government, but a lot of people might call me a government-associated scientist.

Hoover March 31, 2012 at 8:30 am

The way your mind travels from “conservatives have less trust in the leaders of scientific institutions” to “conservatives are anti-science” is a wonder to behold.

dead serious March 31, 2012 at 12:14 pm

I’m sure they’re both true.

The whole assumption that creationism is the answer for human life on Earth and the demand that it be taught in schools has, I think, very little to do with mistrust in leaders of scientific institutions.

Just to name one huge, glaring example.

Benny Lava April 1, 2012 at 10:25 pm

Yes, it is called “reading”. Quite a wonder! You should try it sometime. I suggest you start with anti-science conservatives here: http://voxday.net/archive/2007/030507.html

Neeraj Krishnan March 31, 2012 at 1:33 am

Feynman on science versus ‘science’:
http://www.youtube.com/watch?v=VPunpjeFaiQ
“I know what it means to know something”

Andrew' March 31, 2012 at 8:25 am

A little humility would go a long way. Except then it doesn’t work as a political cudgel.

fogcity1981 March 31, 2012 at 8:30 am

#2… Excellent stuff! If you like thinking about value investing, statistics and baseball, you are going to have a love-hate relationship with Joe Peta’s blog. …I just hate thinking that the Giants have a .500 year ahead of them.

Kirk Hartley March 31, 2012 at 10:09 am

I write as a father and as mass tort lawyer – on the defense side. You can decide what to do with the data below. In doing so, you might also go back to Thinking, Fast and Slow, and its scientific proof that people seek out data to align n their thinking and tell themselves a story of life consonant with the self’s world-view.

Big tobacco started the assault on science with its “doubt” campaign. See generally http://www.defendingscience.org/doubt_is_their_product.cfm. When one tobacco company “flipped” on the others, the jig was up and the coverup was admitted. Controversy was gone and they admitted that tobacco is highly addictive and carcinogenic. Who was drinking the “doubt” kool-aid before the admission there was no doubt.

Today, the “doubt” strategy is used by myriad industries (usually “polluters” or big chemical or pharma) to argue ” we need more studies” and “we can’t say until there is epidemiology – that’s the only “proof”. But you cannot do epidemiology for many things because it would require putting toxins in people, and so there never will be “proof” if “proof” is defined in only one way. Many call it “junk science” if there is no epidemiology.

But, as to “toxins,” that line of argument will fail over the next 5-20 years as molecular biology looks inside our bodies in real time, as highlighted by the Cell paper highlighted last week on this blog. Today, thanks to computers and chip arrays, we can see disease develop at the molecular level, making epidemiology largely pointless except, perhaps, as to cause. Go to ScienceDaily for the Cell article summary and links: http://www.sciencedaily.com/releases/2012/03/120315123016.htm

For today, consider this new article in the “liberal” NYT. http://www.nytimes.com/2012/04/01/magazine/puberty-before-age-10-a-new-normal.html?_r=1&pagewanted=1&hp The article is about “early puberty” in girls as evidenced by early budding of breasts. pubic hair appearing, etc . But in fact, a growing hypothesis is that the this is NOT true puberty and instead is the product of external hormone mimics entering blood systems and terribly confusing the body. The “proof” ? Young girls with budding breasts and pubic hair, but without their pituitary system having kicked in to start the true process of puberty. The advocate – Lustig – is an impeccably trained scientist from and at great schools. BTW, the problems described below were foretold in 1996 by a book known as Our Stolen Future, a book pulling together the science of that day on endocrine disruptors. Here’s a link to a related web site. http://www.ourstolenfuture.org/

Today, the “proof” of endocrine disruptors is emerging. Perhaps ironically, this year is the 50th anniversary of Rachel Carson’s Silent Spring. Key excerpts are set out below from the NYT article on the early puberty situation – decide what you believe:

“Girls who are overweight are more likely to enter puberty early than thinner girls, and the ties between obesity and puberty start at a very young age. As Emily Walvoord of the Indiana University School of Medicine points out in her paper “The Timing of Puberty: Is It Changing? Does It Matter?” body-mass index and pubertal timing are associated at age 5, age 3, even age 9 months. This fact has shifted pediatric endocrinologists away from what used to be known as the critical-weight theory of puberty — the idea that once a girl’s body reaches a certain mass, puberty inevitably starts — to a critical-fat theory of puberty. Researchers now believe that fat tissue, not poundage, sets off a feedback loop that can cause a body to mature. As Robert Lustig, a professor of clinical pediatrics at the University of California, San Francisco’s Benioff Children’s Hospital, explains, fatter girls have higher levels of the hormone leptin, which can lead to early puberty, which leads to higher estrogen levels, which leads to greater insulin resistance, causing girls to have yet more fat tissue, more leptin and more estrogen, the cycle feeding on itself, until their bodies physically mature.

In addition, animal studies show that the exposure to some environmental chemicals can cause bodies to mature early. Of particular concern are endocrine-disrupters, like “xeno-estrogens” or estrogen mimics. These compounds behave like steroid hormones and can alter puberty timing. For obvious ethical reasons, scientists cannot perform controlled studies proving the direct impact of these chemicals on children, so researchers instead look for so-called “natural experiments,” one of which occurred in 1973 in Michigan, when cattle were accidentally fed grain contaminated with an estrogen-mimicking chemical, the flame retardant PBB. The daughters born to the pregnant women who ate the PBB-laced meat and drank the PBB-laced milk started menstruating significantly earlier than their peers.

*****

Adding to the anxiety is the fact that we know so little about how early puberty works. A few researchers, including Robert Lustig, of Benioff Children’s Hospital, are beginning to wonder if many of those girls with early breast growth are in puberty at all. Lustig is a man prone to big, inflammatory ideas. (He believes that sugar is a poison, as he has argued in this magazine.) To make the case that some girls with early breast growth may not be in puberty, he starts with basic science. True puberty starts in the brain, he explains, with the production of gonadotropin-releasing hormone, or GnRH. “There is no puberty without GnRH,” Lustig told me. GnRH is like the ball that rolls down the ramp that knocks over the book that flips the stereo switch. Specifically, GnRH trips the pituitary, which signals the ovaries. The ovaries then produce estrogen, and the estrogen causes the breasts to grow. But as Lustig points out, the estrogen that is causing that growth in young girls may have a different origin. It may come from the girls’ fat tissue (postmenopausal women produce estrogen in their fat tissue) or from an environmental source. “And if that estrogen didn’t start with GnRH, it’s not puberty, end of story,” Lustig says. “Breast development doesn’t automatically mean early puberty. It might, but it doesn’t have to.” Don’t even get him started on the relationship between pubic-hair growth and puberty. “Any paper linking pubic hair with early puberty is garbage. Gar-bage. Pubic hair just means androgens, or male hormones. The first sign of puberty in girls is estrogen. Androgen is not even on the menu.”

Frank Biro, lead author of the August 2010 Pediatrics paper and director of adolescent medicine at Cincinnati Children’s Hospital, began having similar suspicions last spring after he flew to Denmark to give a lecture. Following his talk, Biro looked over the published data on puberty of his colleague Anders Juul. In Juul’s study, some of the girls with early breast development had unexpectedly low levels of estradiol, the predominant form of estrogen in women’s bodies from the onset of puberty through menopause. Biro had seen a pattern like this in his data, suggesting to him that the early breast growth might be coming from nonovarian estrogens. That is to say, the headwaters for the pubertal changes might not be in the girls’ brains. He is now running models on his own data to see if he can determine where the nonovarian estrogens are coming from.”

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