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GMOS and Crop Yield

There was an interesting paper published last week in Nature Biotechnology by some University of Wisconsin professors of agricultural economics and agronomy (by the way, one of the authors, Chavez, is a preeminent agricultural economist - he's also one of the most well read economists I've ever been around).

The study used crop yield data from plots in Wisconsin and showed that not all biotech corn varieties outperform conventional varieties in terms of yield.  As they put it:

Compared with conventional hybrids, the impact of transgenic traits (both single and stacked traits) on mean yield ranges from −12.2 to +6.5 bushels per acre.

Not surprisingly, the result has been picked up by the anti-biotech crowd, such as Tom Philpott at Mother Jones.  

According to the biotech industry, genetically modified (GM) crops are a boon to humanity because they allow farmers to "generate higher crop yields with fewer inputs," as the trade group Biotechnology Industry Organization (BIO) puts it on its web page.
Buoyed by such rhetoric, genetically modified seed giant Monsanto and its peers have managed to flood the corn, soybean, and cotton seed markets . . .
Turns out, though, that both assertions in BIO's statement are highly questionable.

There are numerous problems with Philpott's arguments.

First, is rhetorical.  Monsanto didn't "flood the market."  Somebody had to buy those seeds.  Those somebodies were farmers who willingly adopted, and even paid price premiums to have biotech seeds.  Which leads to the second issue.

As the Nature Biotechnology study shows, the biotech varieties had an important risk-reducing effects, even if they sometimes led to slightly lower yields.  Moreover, biotech can save on other inputs like labor.  When I was a teenager, I spent a lot of time hoeing and spraying cotton weeds. That job is (thankfully) now obsolete due to biotechnology.     

You also can't just cherry-pick the results you want to emphasize if you want to actually be objective.  As I reported earlier, larger studies conducted over a much wider geographic region DO show yield improvements from biotech adoption (though that study shows - like the more recent one in Nature - that yield effects of traits are not additive).  Moreover, check out table 1 (gated) of the aforementioned study in the American Journal of Agricultural Economics, which shows 31 different results from numerous studies, almost all of which show a yield boost from biotech.  Or see this study in Science by another preeminent agricultural economist showing significant yield gains (and pesticide reductions) from biotech adoption in India.  The totality of the evidence suggests that - in most locations and for most crops - biotech does increase yield most of the time (though not always and not in all locations and not for all crops).

That gets to my last issue with Philpott.  He (and others) continually reference the work of Charles Benbrook on pesticide use associated with biotech.  But, rarely do they differentiate between pesticides use (which biotech DOES reduce) and herbicide use (which biotech has increased).  Also ignored is the relative toxicity and environmental effects of pesticides vs. herbicides or the reduction in toxicity that has occurred over time as a result of biotech (see this recent critique of Benbrook's work).  If that weren't bad enough, such authors also fail to point out that use of herbicide-resistant biotech facilitates no- and low-till farming practices, which are a real environmental benefit (indeed, the data shows that biotech adoption is strongly correlated with no- and low-till adoption).  

I'm not saying there are no downsides to biotech use (e.g., more rapid development of herbicide resistant weeds; potential market power in the seed/chemical sector).  But, one has to look at the totality of the evidence and not just cherry-pick.  Moreover, you have to look at the decisions made by real-life flesh and blood farmers all over the world who have voluntarily adopted GMOs.  The fact that biotech was so readily adopted by farmers (and is still so widely in use) aught to tell you something.  

Fast Food Restaurants Getting Healthier

One of the reasons I’m often critical of government policies that attempt to force healthy eating on the public (say through ingredient bans or fat taxes) is that I have a different view of “Big Food” than many foodies.  Big Food is often portrayed as powerful, nefarious entity preying on helpless consumers.  I’m more apt to seeing fast food restaurants as responding to consumer demand for convenient, inexpensive, quick food.  They offer burgers and fries because this is what consumers are willing to pay for. 

However much we may want McDonald’s et al. to offer healthier alternatives, at the end of the day they must make enough money to stay afloat.  If more salads are offered than consumers want or are willing to buy, that’s a recipe for disaster.  As one organic farmer put it: the first rule of sustainability is that you have to make enough money this year to do it all over again next year.  I have little doubt that the McDonalds of the world would offer a lot more salads if they thought they could make money doing it. 

Against this backdrop, I noticed a recent study by the Hudson Institute that examined the offerings of fast-food restaurants over the past five years (it was covered by the WSJ here).  Here’s what the study found:

“between 2006 and 2011, lower-calorie foods and beverages were the growth engine for the restaurants studied. In 17 of the 21 restaurant chains evaluated, lower-calorie foods and beverages outperformed those that were not lower-calorie. In addition, chains that increased their servings of lower-calorie items saw positive returns as a result. These chains generated:

  • a 5.5 percent increase in same-store sales, compared with a 5.5 percent decline among chains selling fewer lower-calorie servings;
  • a 10.9 percent growth in customer traffic, compared with a 14.7 percent decline; and
  • an 8.9 percent increase in total food and beverage servings, compared with a 16.3 percent decrease.”

The lesson is that you don’t always need government regulation.  The market will deliver healthy foods when the public decides that’s what they want.

Does Organic Food Cause Autism?

Of course not.  But if you applied the same logic used by many anti-GMO activists who claim that the increased use of GMOs caused the rise in autism, one would have to claim that the of organic food also caused autism.  That's according to this post by Kevin Folta.  

His little parody shows how easy it is to create a scary sounding food story based on spurious correlations.  In fact, he shows three graphs illustrating the rise in autism, the rise in diabetes, and the rise in organic food consumption over time.  All three track each other almost perfectly.  But no one reasonable would claim that diabetes causes autism or that organics cause autism.  Likewise, no reasonable person should claim GMOs cause autism unless they can provide some causal biological biases for the claim.  

It is exactly this sort of fallacious correlational analysis that "suggests" adoption of GMOs in India caused an increase in suicides.  This little tidbit spread like wildfire around the web, made its way into food documentaries, and now is often repeated as fact.  The trouble is that when you actually look at the facts, the story doesn't hold much water.  

Here are the first two paragraphs of Folta's parody:

While people think of "organic" cultivation techniques as natural and safe, there are important points we might consider.  Most of the plants used today have only been developed genetically in the last 100 years, and even "heirloom" varieties were bred relatively recently.  There have been no long term studies, and plants certainly are known to produce a wide suite of toxic compounds.  
Worse, organically cultivated plants are placed in highly artificial environments.  Rather than growing in soil as it exists, soils are highly amended with composts and manures. High levels of nitrogen and carbon dramatically alter gene expression leading to patterns never observed in nature. Van Djik et al. (2012) found that there were dramatic differences in gene expression between conventional and organically-grown potatoes, with organic potatoes showing higher expression of stress-related genes. There have been no long-term studies to assess the effects of this un-natural gene expression. 

The Next Food Technology Worry?

It's nanotechnology.  A blog post at Scientific American raises concerns about the use of nanotech in food.  According to the piece:

A new report from an environmental health group, As You Sow, raises concern about nanoparticles in some popular sweets. The group says it found particles of titanium dioxide less than 10 nanometers in size in the powdered sugar coating on donuts from Dunkin’ and Hostess (now sadly defunct). The group argues that the nanoparticles have no business in any kind of food until safety testing is done; in this case, the tiny bits could make donuts even unhealthier.
Nano-sized particles, roughly one-billionth of a meter in diameter (much smaller than the width of a human hair), have been in food for decades at least, often an unintentional byproduct of processing techniques. But a whole range of novel nano-sized particles—ranging from tiny flakes of titanium dioxide to whiten powdered donuts to submicroscopic silver bits to kill microbes—are showing up today in food and food packaging on purpose.

Are these nanotechnologies dangerous?  I don't know.  I do know scientists have been working for years on a variety of nano-tech developments and many products we use today (particularly sunscreen) have nanoparticles.  

It will be interesting to see if nano-tech becomes the next bio-tech in attracting controversy.  I suspect it will be harder to vilify nano-tech foods (should we call them NTFs?) relative to GMOs.  The reason is that many of the nanotech developments were developed specifically with the consumer in mind to make their end-experience better by improving shelf life (often through improved packaging), nutrition, and taste.  These are much more tangible benefits for the consumer than the harder-to-see benefits that have accrued via food biotechnology (mainly reduction in the price of food).  Moreover, unlike GMOs, for NTFs it will be harder to find a company like Monsanto around which conspiracy theories can form.