OK, everyone have a seat and take a few deep breaths. Go to your calming place. Ready? Good. Because I’m about to talk about a new study that suggests that eating genetically modified crops might not be the best thing for us.
OK, another deep breath. I know what you’re thinking. You’re thinking, “Tom, didn’t we settle this issue already?” After all, as the “plant science” industry group CropLife — you know, the one that hates First Lady Michelle Obama — likes to say, “more than 150 scientific studies have been done on animals fed biotech crops and to date, there is no scientific evidence of any detrimental impact.”
You’ll remember, I’m sure, the recent brouhaha over a French study by scientist Gilles-Eric Séralini that purported to find evidence that a GMO-based diet caused tumors in rats. Critics immediately raised significant questions about that study and the consensus quickly became that it was poorly conceived and executed. It was also the study that caused several science writers to conclude that anti-GMO sentiment was the moral equivalent of climate denial. Good times.
So is this new study [PDF], as the critics are already asserting, “L’affaire Seralini” redux? Let’s take a look.
Australian scientists, working with an Iowa farmer and U.S. veterinarians, studied 168 “commercial” piglets as they were raised and fattened for slaughter. Half of the pigs received non-GMO feed and another half ate feed made from GMO corn and soy. Researchers made sure that the GMO feed contained multiple kinds of genetically modified grains that are common in livestock feed; one grain was raised from seed that is herbicide-tolerant, for example, and another from seed that expresses its own pesticide. (One of the complaints of past GMO feeding trials is that they did not reflect actual feeding practices and thus couldn’t account for any potential “synergy” from exposing animals to more than one of these so-called “transgenes.”)
The vets who examined the pigs post-mortem didn’t know whether they were looking at an animal raised on GMO feed or not — to preserve the “blind” nature of the study.
The results, as reported by Reuters:
Researchers said there were no differences seen between pigs fed the GM and non-GM diets for feed intake, weight gain, mortality, and routine blood biochemistry measurements.
But those pigs that ate the GM diet had a higher rate of severe stomach inflammation — 32 percent of GM-fed pigs compared to 12 percent of non-GM-fed pigs. The inflammation was worse in GM-fed males compared to non-GM fed males by a factor of 4.0, and GM-fed females compared to non-GM-fed females by a factor of 2.2. As well, GM-fed pigs had uteri that were 25 percent heavier than non-GM fed pigs, the study said.
So what are we to make of this?