Science Vs - GMO... OMG?

Episode Date: April 17, 2017

Science Vs peels back the label on GM foods to find out whether they’re safe to eat and what impact they can have on the environment. Both sides of the debate have written impassioned songs, but what does the science say? We talk to Prof. Fred Gould, Dr. Janet Cotter, and Prof. David Douches to find out. ***Please note*** this episode has been updated. In the original version we suggested that the Bt corn that killed monarch caterpillars was taken off the market as a direct result of studies demonstrating its harm. But although the corn was eventually taken off the market, the company that made it later told us it was phased out "for business reasons", such as declining sales -- and they did not mention the dead butterflies. Credits: This episode has been produced by Shruti Ravindran, Heather Rogers, and Wendy Zukerman. Our senior producer is Kaitlyn Sawrey. Production assistance by Ben Kuebrich. Our editor is Annie-Rose Strasser. Fact Checking by Michelle Harris and Ben Kuebrich. Music production, mixing and original scoring by Bobby Lord. Thanks to Professor Elizabeth Ransom, Professor Stephen Long, Stephen Tindale, Dr Chuck Benbrook and Joseph Lavelle Wilson. Our Sponsors:Ziprecruiter - Try Ziprecruiter for free by going to ziprecruiter.com/sciencevsCloudflare - To learn more visit cloudflare.com/sciencevs Further Reading:The National Academy of Sciences report on GE cropsOur favourite youtube videos about genetically modified crops here, here and here.  Learn more about your ad choices. Visit podcastchoices.com/adchoices

Hi, I'm Wendy Zuckerman and you're listening to Science Versus from Gimlet Media. On today's show, genetically modified foods, or GM foods. Are they going to help feed us in the future? Or are they a danger to our health and our environment? Well, here is a story that will make your stomach turn. The report claimed that 200 rats fed GM corn produced by US firm Monsanto had suffered tumours as big as ping pong balls. It's pretty appalling. You're talking about liver damage and kidney damage. When it comes to GM foods, there is a lot of scary news out there.

And all of this has people worried. 57% of Americans said in a 2015 Pew poll that GMO foods are, quote, unsafe to eat. And in 2015, half of Europe banned their farmers from growing genetically modified crops. The controversy surrounding genetic modification is so strong that it's even got people writing protest songs. I'm looking at the food that's in the grocery store. They say it's safe, everybody eat more.

On second thought, I don't really know. It was made with those GMOs. Just say no to GM. Uh-oh. But not all songs are anti-GM. In fact, some YouTubers are singing a totally different tune and they are very excited about the potentials of this technology. They're singing that it will help feed our growing population. They just don't make protest music like they used to. We have the means to engineer these dreams.

Ugh, they just don't make protest music like they used to. Where is Kendall Jenner when you need her, eh? We are the chosen. Despite the songs and the news reports, GM crops continue to be grown across America. Half the land used in crop production in the US is planted with GM crops continue to be grown across America. Half the land used in crop production in the US is planted with GM crops, a lot of which ends up in the bellies of livestock, but some of which ends up in our bellies.

When it comes to genetic modification, there are lots of opinions and ridiculous songs on YouTube. But then there's science. Science vs GMO is coming up. I want to know if it's verified so I don't harm myself. Genetically modified. Y'all afraid of ghosts? How about ghost peppers?

It's the moment you've been waiting for. The ghost pepper sandwich is back at Popeyes. A buttermilk-battered chicken breast served on a brioche bun with barrel-cured pickles. And here's the best part. It's topped with a sauce made from ghost peppers and oncho chilies. If that doesn't send a chill of anticipation down your spine, nothing will. Get your ghost pepper sandwich today at Popeyes before it ghosts you for another year. So what's it like to buy your first cryptocurrency on Kraken? Well, let's say I'm at a food truck

I've never tried before. Am I going to go all in on the loaded taco? No, sir. I'm keeping it simple. Starting small. That's trading on Kraken. Pick from over 190 assets and start with the 10 bucks in your pocket. Easy. Go to kraken.com and see what crypto can be. Not investment advice. Crypto trading involves risk of loss. See kraken.com slash legal slash ca dash pru dash disclaimer for info on Kraken's undertaking

to register in Canada. At Wealthsimple, we're built for whatever you're building. Built for Jane, who wants to break into the housing market. We're built for Ted, who's obsessed with what's happening in the global markets. And built for Celine, who just wants to retire and explore the world's flea markets. So take a moment and think about what you're building for. We've got the financial tools to help make it happen. Wealthsimple. Built for possibilities. Visit wealthsimple.com slash possibilities. Welcome back.

Today we're heading into the controversial world of genetically modified organisms. We're asking first, are they bad for our health and the environment? And second, we're looking at the benefits of GMOs and asking, are GM crops producing bigger harvests? And so, will they help us feed our growing population? To start off though, let's explain how GMOs work. And to do this, we called in a pro. But then along came a man and a microscope and he separated the genes. No, no, no, not him.

Sorry, these songs are just too good. We are talking to Fred Gould, a professor at North Carolina State University, and his specialty is actually entomology, the study of bugs. Do you have a favorite bug? Oh, that's such a hard question. There are so many to choose from. Well, I guess praying mantises are probably my favorite. How come?

Well, they're just so human-like, actually. You know, watching them lay eggs and watching their young hatch out, it's just always amazing. Yeah, just as they lay their eggs and hatch them, they're just so human. Anyway, the reason that we're talking to Fred is because he was the chair of the National Academy of Sciences report, which came out earlier last year on the risks and benefits of GMOs. It's a big thumper of a report, and it fact-checked 20 years of claims about GMOs. The good, the bad, and the ugly. And just personally speaking, Fred really gets that people have concerns about food.

So I should just tell you that I'm 67 years old now, and I've been a vegetarian since I was 19. So it's not like I just eat everything. Now, when you talk about GMOs, Fred tells us there's one really important thing that you have to understand right off the bat. And that is this. There are different types of GMOs that work in different ways. But we're just going to focus on a couple of these types in this episode. There are only really two major traits that have been added to these crop plants. And those are the trait of being resistant to insect pests and being resistant to herbicides.

So let's really break these down. First, crops that are resistant to insects. To make these GMOs, scientists extract a gene from a bacteria that lives in soil and then smush that gene into a crop's genome. Now, this means that the GM crop will now pump out a protein called BT, which is toxic to particular insects. These are very specific proteins that only affect a very small number of insects.

Now, when these sensitive insects chomp on the crops, the protein disrupts their digestive system and it can kill them. And Fred says sometimes the insect just gets so sick on the first bites that they stop eating the plants. Some of the most common varieties of insect-resistant crops are corn and cotton. Next, Fred tells us about the second popular trait of GMOs. OK, so the crop is engineered to be resistant to a specific herbicide. Now, this means that farmers can spray herbicide onto weeds that have invaded their farms without killing their crops.

Here's how it works. There's a powerful weed killer called glyphosate and it latches onto a critical enzyme in plants and kills them. Now, this is great for farmers trying to kill weeds, but the problem is that it kills practically all plants, and that would include the crops that farmers are actually trying to farm. So here's where the genetic modification comes in. So what they did was they engineered the corn or the soybean or the cotton so that you could spray the glyphosate on them

and they wouldn't be harmed. So it would only kill the weeds. So scientists have modified a bunch of crops so that glyphosate can't latch onto its enzyme and kill it. And those GM crops can survive even when they're sprayed and sprayed with glyphosate. Indeed, the most common herbicide-resistant crop is made by Monsanto, and it's called Roundup Ready.

Cue the music. Roundup! I'm a loving husband and a real good dad, but weeds just make me rattlesnake mad. Now Roundup has a new sharpshoot wand, I'm sending them weeds to the great beyond. Roundup! Yeah!

Conclusion. There are two different traits of GMOs that are in widespread use around the world. One is modified to be insect resistant and the other has modified plants to be herbicide resistant. And this takes us to our first big question. What are the risks here? That is, what is all of this genetic modification doing to you and me? We're going to start by looking at that study that you heard at the very beginning of the show, the one that sent the media into overdrive, and it was published back in 2012. A recent European study found that rats fed a GM diet over their lifespan suffered mammary tumours and severe liver and kidney damage. The report claimed that 200 rats fed GM corn produced by US firm Monsanto

had suffered tumours as big as ping pong balls. A photo of a scientist holding up fat white rats with these horrifying big tumours spread like wildfire across the internet. And that scientist that was holding up those rats was Gilles-Éric Seralini, a professor at the University of Caen. Now, to get those terrifying results,

he took 200 rats and divided them into several groups. Some rats were fed GM corn, the herbicide-resistant kind. And the others were fed a non-GM corn. And they were on this diet for around two years. Here's the scientist that conducted this controversial study, Gilles Eric. We found that the rats fed with the GMO had a lot of mammalian tumors. They were becoming big and hemorrhagic. When Gilles Eric tallied up the deaths and the tumors, he found that the rats that ate GM corn developed more tumors and died earlier than those who

didn't. So in comparison to the control, there was three to five times more tumours and we demonstrated the toxicity very nicely. After that rat study, Gilles Eric wanted to know, how was it that herbicide-resistant corn could cause tumours? So to find out, he ran a bunch of tests, this time on the GM corn itself, and he found that the genetic manipulations had created tiny chemical changes in the make-up of the corn.

Gilles Eric now believes that those tiny chemical changes are harmful for rats and trigger processes in their body that produce tumours. To Gilles Eric, this is all strong evidence that GM corn is dangerous. So now we have confirmed and confirmed by several papers how and why we were right. So, this is all potentially scary. Rats with tumours, chemical changes that are maybe causing cancer?

But there are a couple of things you need to know here. First, that big NAS report said that tiny chemical differences are often found in different seeds, whether they're genetically modified or not. And ultimately, it concluded that when it comes to those chemical changes, they, quote, do not on their own indicate a safety problem, end quote. And what about that rat study, the one that was so shocking? There were lots of problems with it. The type of rat that Gilles Eric used was called a sprag dolly, and they're known to spontaneously develop tumours when they get older. So the average number of tumours that he found in

his GMO-fed rats was actually really similar to what other teams have found in rats munching on a non-GMO diet. So the fact that Gilles Eric's GMO rats ended up with more tumours could just be by chance. And that takes us to the second problem with this study. The statistics that Gilles Eric used were heavily criticised, so much so that according to that NAS report, when the European Food Safety Authority reanalysed the data, it didn't find statistically significant differences between the rats who ate the GM corn and those who didn't.

We went through all of these criticisms with Gilles Eric, like that the study hadn't been replicated. But he stuck to his guns. This is just one study, it's not conclusive. I mean, that is true. No, it's not. It is highly conclusive. I mean, that is true. No, it's not. It is highly conclusive. And I told you that we have proven that it was highly conclusive. And those criticisms?

Well, he said they came from people who were biased and pro-GM. Our producer, Shruti Ravindran, asked him about it. So you're saying that any criticism you've had is because people have their corporate biases? No, it is a little bit more complicated than that. All the criticisms, I can accept. Science works like that, the criticisms. But they must be serious. And to be clear, he didn't count the criticisms that we just talked about as serious.

He said it was all from the pro-GM groups. Well, the lobbies, because they were the lobbies, said a lot of stupid things about that. Yes, there are issues with lobby groups and the way that companies that develop GM crops run. Companies like Monsanto. Many of these companies are notoriously secretive and they don't make it easy for

independent researchers to study their seeds. And a lot of people working in this space have worked for big GM companies or have ties to them, so it can bias their results. This is a problem and we do need more independent studies. But still, there are many scientific reasons to doubt Jill Eric's work, and that's what we're doing here today. We're just going to focus on the science and to try to figure out what the current peer-reviewed research on GMOs says. The journal that published Jill Eric's study ended up retracting it, and so far, no other groups have found anything similar. Conclusion. While Gilles-Eric Seralini's work made some very impressive headlines and scared a lot of people into thinking that GMOs can cause cancer, that work has largely been discredited. So, we need to look for more studies by different groups to find out if eating genetically modified crops is dangerous.

Fortunately for us, that big National Academy of Sciences report, the one that Fred worked on, did just that. We took this very seriously and we went back to almost all of the original studies and looked to see what the evidence looked like. So we looked through four different kinds of evidence. They looked at animal studies, chemical analysis of GMOs, studies looking at the health of livestock eating GM crops,

and then they looked at the biggest natural experiment of all, one happening in us humans. In the US and Canada, people have been eating foods that contain genetically engineered ingredients since 1996. That's basically 20 years. And in the UK and in the EU, people haven't been eating those crops. Well, Europeans do eat some GM foods, but it's not that much, particularly when you compare it to people living in the US.

So when he looked at all of those studies, what did Fred's NAS report find? Basically, what we could say was we found no evidence in all of these studies that the safety of eating food that comes from genetically engineered crops that are commercially produced today is any different than the safety concerns over eating conventionally. Yes, the big NAS report found that while cancer rates over time have changed, those changes were generally similar in the US, the UK and Europe. And that's why the NAS ultimately concluded that cancer rates, quote, do not appear to be associated with the switch, end quote, to GMOs. Now, what about those other issues like obesity,

gastrointestinal problems, allergies, autism? Could GM foods cause these? Well, again, by comparing the United States to Europe, the NAS report found no convincing evidence of a link between GM foods and any of these health problems. Conclusion. The best evidence that we have tells us that there is no harm to eating currently approved genetically modified foods. Now, this conclusion doesn't address people who have to deal with glyphosate, the weed killer, every day, like farmers, for example. And there are studies that show an increased

risk of non-Hodgkin's lymphoma for people who regularly handle that weed killer. So those are the health risks. But next up, what about the risks to our environment? Janet Cotter was invited to present her concerns regarding GMs to the National Academy of Sciences Committee. Hello there. Hello. Is this Janet? Yes, it is. Hello there. Hello. Janet worked for Greenpeace for decades and is now a consultant for many environmental organisations, including GM Freeze, which campaigns for a moratorium on GM in food and farming in the UK.

Now, before she got into the advocacy business, Janet was a scientist, a soil scientist. Soil's fascinating. You're the skin of the earth, if you like. And it's just so enormously complicated and complex. I mean, I think it's been said that we know more about outer space than we do a teaspoonful of soil. And Janet's shift from scientist to advocate

started when she spotted some anti-GMO protesters outside a supermarket. It got her thinking about the potential unintended consequences of GMOs to our environment. You know, the more I kind of looked into it, the more I thought, wow, hmm, I'm not sure I'd really want to have this stuff grown outdoors. I was thinking, well, there's not really complete understanding of the science

involved here. Janet's big concern when it comes to GMOs in the environment is that genetically modified crops can reduce biodiversity, which is the variety of plants and animals in a particular ecosystem. Now, ultimately, Janet believes that GMOs are killing off and harming more plants and animals than traditional farming does. Yeah, exactly, exactly. You are damaging that biodiversity. She says that while some GMOs are designed to kill certain insects that are pests, they could be killing other insects too. So the insect-resistant corn was found that it could affect organisms

other than the pest it was designed to be toxic to. And her best example to illustrate this point is what happened to the monarch butterfly. If you've ever purchased something that's verified non-GMO, say tortilla chips or hand cream or milk, you've probably seen a tiny symbol of an orange butterfly landing on a bunch of grass. And that's because the monarch butterfly is to GMOs what the polar bear is to climate change. Very cute, very symbolic and guaranteed to make a bunch of people very angry when it's in danger.

And concerns about GM foods and the monarch butterfly go back to the late 1990s. The very same year that Crazy Town's butterfly came out, in 1999, a study was released which found that a particular kind of GM corn was toxic to monarch butterflies the very same year coincidence we think not the particular corn that we're talking about here was insect resistant, so it had that BT protein in it that was designed to kill pests. But it was also toxic to monarch caterpillars. When the little caterpillars ate leaves dusted with GM pollen,

nearly half of them died within four days, much more than those exposed to non-GM pollen. And these deaths really freaked people out. So scientists quickly went about trying to replicate the findings. And they did. Now, that corn was eventually taken off the market. But the company that made it told us that it was phased out, quote, for business reasons, end quote,

such as declining sales. And they did not mention the dead butterflies. That earlier research with its frightening findings has left Janet convinced that even new varieties of GM crops must be doing some harm. And that for me was a real light switching on moment that, you know, we need to actually look very carefully at these things. Janet told us about another study, one from 2004, that exposed two groups of caterpillars to pollen from BT corn varieties, ones that are still on the market. And they found that caterpillars exposed to the GM pollen were less likely to reach adulthood. You know, so the

dangers of actually sort of meddling with those really quite intricate systems, you could actually give rise to an effect that you weren't maybe expecting. Now, that might be concerning, except for the fact that the researchers who actually did the study said in their own paper that only a fraction of the butterfly population would be affected by this. And they ultimately concluded that, quote, it is likely that BT corn will not affect the sustainability of monarch butterfly populations in North America, end quote. We spoke to Janet about this and pointed out what the researchers said. And she said, OK, sure, maybe they won't all die this way, but there could be other unintended consequences that we haven't measured yet.

I'm thinking here about something that may not actually say kill a butterfly, but it may impair its reproduction or something like that. That could lead to a long-term effect. What amount of studies or what kind of studies would ultimately make you feel comfortable? I don't think there are any amount of studies I don't think would satisfy the fact that doubts will linger, basically, because it's impossible. It's like looking for a needle in a haystack, basically, if you're looking for an unintended effect.

Ultimately, that big NAS report noted that the monarch populations have actually been declining over the past few decades. But the authors say that it's really hard to pinpoint exactly what is causing that. And so far, according to our best evidence, there is no consensus that GMOs are to blame. Conclusion. Some butterflies in the late 1990s and early 2000s did die as a result of GM crops. But since then, there hasn't been any conclusive evidence that GM crops are significantly affecting butterfly populations. In fact, that NAS report didn't just look at butterflies.

It looked at a range of creepy crawlies, spiders, beetles, leafhoppers. And it found that when it came to insect biodiversity, there actually were benefits to GMOs or transgenic crops. And we did find in most of the studies, there was more insect biodiversity in the fields where the transgenic crops were used. But why? How could genetically modified fields have more biodiversity in them than fields with regular crops? And will GM foods help feed a growing population? Because this man surely thinks so. Genetic modification

More bad music and the benefits of GM, coming up just after the break. After decades of shaky hands caused by debilitating tremors, Sunnybrook was the only hospital in Canada who could provide Andy with something special. Three neurosurgeons, two scientists, one movement disorders coordinator, Welcome back. So we've looked into the potential risks of GMO and though there are still some unknowns, we found no conclusive evidence that GMOs are a risk to our health or the health of our environment.

Now it's time to look at the other side of the issue, the benefits. First up, let's look at why other side of the issue, the benefits. First up, let's look at why, as you just heard before the break, fields grown with GMOs have more insect biodiversity than non-GM fields. To talk us through this, we met Dr David Douches at his lab. David's a potato geneticist at Michigan State University. Not to sound sappy or anything, but actually I've always wanted to be a vegetable breeder. I've always thought that the concept of genetic improvement and I wanted to work on vegetables since I was a young kid. And so this is really, for me, to do this work is really a dream come true. And his lab doesn't look like a regular science lab.

There's big trucks, farming gear and racks and racks of potato chips. And here's what you need to know about David. He's mad for potatoes. The shelves of his office are crowded with plastic Mr Potato Head toys, a whole army of them sporting oversized glasses and top hats and Santa hats. And senior producer Caitlin Sori even saw signs of potato loving on his car. Your licence plate says spuds. Yeah.

He showed Caitlin around the lab. So we just walked into a room. It's all very bright white lights and like hundreds of tiny little rows of plants ready to be grown. What are these guys? We just opened up a fridge. So this is not a fridge. This is actually a kind of a growth chamber. This growth chamber lets plants grow in pretty perfect conditions so David can study them as they grow. And David says that the GM projects he's working on

are going to make potatoes healthier, cheaper and easier to store and distribute. These potatoes that I see in the future will blow the doors off of the ones that we're currently growing. David is really proud of a particular project he's worked on, a late blight resistant potato. Late blight is kind of like a fungus and it's what caused the Great Potato Famine in Ireland in the mid-1800s. This famine killed more than a million Irish people.

So yes, cue the sad Irish music. I think that's just Irish music. Anyway, even today, this fungus remains the potato farmer's biggest nightmare. It costs the world's potato farmers $5 billion a year. So farmers try their best to ward it off, and they can end up spraying their fields more than a dozen times in three months to kill the blight. But David's GM potato isn't affected by late blight. And that's why potato farmers reckon David's a fun guy. Get it? He's a fun guy because he kills fun guy. So when you plant two types of potatoes side by side, one genetically modified and one not, and they're both exposed to late blight, it's phenomenal the difference. I mean, the one that's infected that's not GM is this spindly little, I mean, it's dead.

And then on the other side is this beautiful, healthy plant. I remember when we got our first late blight resistant potatoes and it was very exciting. We had these little islands of green that survived the pathogen out there. And these islands of green didn't need extra chemicals to keep them healthy. Which takes us to a quite surprising benefit of GMOs. Planting them has meant that farmers don't have to spray so much pesticides on their crops. Yes, while you won't hear about it in rap songs on YouTube,

growing GMOs can mean less chemicals are being sprayed on crops. When we look at the effect of planting insect-resistant crops, that comprehensive National Academy of Sciences report said, quote, overall use of insecticides on maize and cotton in the United States has decreased, end quote. Here's Fred. Overall, the amount of spraying of insecticides has decreased, and that's very true in countries like India and China, where they used to spray a huge amount of insecticide in cotton. The only thing that was open to question was how much less insecticide was being used. Now, different crops in different fields around the world had different results.

Some showed farmers used around 70% less insecticide, others used around 40% less. And this, this is why when studies look at the insects, the bugs, and the beetles, as well as the spiders, they find that on average fields of GM crops designed to be insect resistant have more insect biodiversity than conventional crops because farmers are spraying less insecticide on them. The NAS report pointed to one study from China that found more ladybugs, lacewings and spiders in fields with BT cotton than those with regular cotton.

And who doesn't love ladybugs? They're so cute. Conclusion. Ah, whoops. Okay, we got to get really into the weeds here because there is still that other type of GM crop that we have to talk about. That's the Roundup Ready crops. They are designed in a totally different way. Remember, they're designed to be resistant to weed killer. So farmers can go to town spraying their crops for weeds and they don't kill off the crop.

And this, this is where our story of less chemicals changes. The NAS report found some studies showing that more pounds of herbicide were being used on these crops, but other studies didn't find that. And ultimately, the NAS report wrote that when you're concerned about safety and the environment, the amount of herbicide that you use isn't the only important thing here. It's also important to look at whether the herbicide that you're using is more toxic or not. And for now, it's just not clear that the weed killers used on GM crops are more dangerous than other weed killers that farmers use.

Conclusion. When GM crops are designed to kill insects and other pests, like late blight, farmers spray less chemicals on their crops, and that means more creepy crawlies in the field. But when GM crops are designed to be herbicide-resistant, it's not clear if they're using less chemicals on their field and whether those chemicals are more dangerous.

Next question. In the GM farms where farmers are using less pesticides, can the good times last? Because scientists are now finding that the insects and the weeds are adapting to the once toxic GM crops. Yes, they're becoming super bugs and super weeds. These are weeds that won't die when they're sprayed with that particular weed killer, glyphosate.

And these super bugs won't die when they munch on the GM crops. And this resistance problem is so bad that Fred Gould, who helped write that big NAS report, calls pest resistance... That's the biggie, OK? And I would say that the overuse of these technologies has led to some insects becoming resistant. One of those little guys who's developing resistance and could be a canary in the coal mine is known as the bullworm.

Most of the bullworms in the U.S. are on corn and cotton and soybean. I just did a Google search. It's kind of cute. It's got like these little stripes on it. Tell that to your neighbor when they buy corn in the supermarket and have a caterpillar jump out at them. But I think it's cute too. Thank you. Now, the NAS report did say that this super bug and super weed problem could be avoided by using some farming practices that might delay or prevent resistance. But this arms race will no doubt continue. Fred told us that there were even new varieties of GM crops that were being developed that could be sprayed

with more than one weed killer so that farmers can attack the super weeds with their now super GM crops. It sounds like it's a recipe for more pesticide use. Yeah, so it does sound like that. You know, I'd want to see what actually happens. I think the jury's sound like that. I, you know, I want to see what actually happens. I think the jury's out on that. Conclusion. Insects and weeds are evolving to live and thrive amongst GM crops. So the benefits we've seen from GM, less insecticide use,

more biodiversity, may not last long. And this brings up another question about the long term. And that is, will GMOs be the food of the future? With populations increasing and resources shrinking, will GMOs increase the amount of food that we can grow so that we can feed our growing population? Because that's what the GM companies are saying. Our researchers and breeders develop products that help farmers have better harvests while using resources more efficiently. Genetically modified crops are just one of the ways we're

doing this. On websites where these crops were heralded as being very important for society, often it was in this sense of we need to feed the world. But do genetically modified crops really produce more and bigger crops? When we look at all crops, GM and non-GM, Fred Gould points out that as farmers in the US are getting better and better at growing crops, their overall yields have increased in the last few decades. You know, there's always been this thing out there that genetic engineering would help these increases increase faster. And so we were expecting that.

They were expecting it. But did farmers that went GM pump out more crops than non-GM growers? In the aggregate data, we don't see that. And in a certain way, that's surprising. The NAS report looked at data on corn, cotton and soybeans across the United States and found that GM varieties have not, on average, produced more than conventional crops. So, according to the research, the promise of bumper GM harvests just hasn't panned out.

But Fred says there is some nuance here. So in areas where insects were a problem and plants were genetically modified to resist those insects, there actually was an increase in yields because those bugs couldn't munch on the crop like usual. And that kind of makes sense because that's what the crops were designed to do. But no pests around, no yield benefit.

Conclusion. GM crops aren't radically increasing the amount of food that farmers can grow. Yet. There are hopes, though, that GM crops could do much, much more in the future. You could design a plant to grow in the shade, survive drought, be more nutritious or even just grow more. Recently, eucalyptus trees were genetically modified to grow 20% more tree. For the moment, though, there's all this promise, but most of these plants haven't made it out of the lab.

So whether they can really feed the world in the future, we'll just have to wait and see. Do we need these to feed the world in the future? No one thing is the key to solving world hunger. Could genetic engineering help in solving world hunger? I think that's very feasible, and it'll depend on what kind of products are developed and how they're used. And feeding the world is a pretty complicated story. It isn't just solved by making a whole bunch more food. The food has to get where it's needed, people need to be able to afford it,

and we need to stop wasting that roughly 30 to 40% of the food that we currently waste. So, when it comes to science versus GMOs, do the fears and the promises stack up? First, the risks. While there are lots of health concerns out there, none of them have been scientifically proven. How about risks to the environment? Genetic modifications do have the potential to do harm, like that particular strain that killed the butterflies.

But as for the GM crops currently in use, for now, we don't have good evidence that GM crops are harming the environment. In fact, there is evidence that GM crops can reduce insecticide use, which means more insects and more insect biodiversity. Although, enter the superbugs, we don't know how long this will last. As for yields, for the moment, GM crops have not increased yields overall. But if they're designed to kill certain pests, and those pests are around, then yeah, you do get more crops. After all of his research, I asked Fred Gould,

what do you put in your mouth? Do you eat GM foods? I certainly eat genetically engineered foods and I would feed such a thing to my grandchild. So while GMOs certainly haven't fulfilled many of their promises of growing superfoods and feeding the world, they also aren't proving to be that harmful, which kind of makes me wonder why so much fear, anger, and bad rap music. Well, a lot of this seems to be fear of unknowns or fear of new technologies. And Fred Gould understands that modifying foods in laboratories might seem scary, but according to the best science we have, it's just not. And yet, it's still our bogeyman.

Fred says that every age has its bogeyman. And maybe ours is scientists playing with genetics in labs. Look at all the science fiction movies you see these days, and where does genetic engineering come in? You know, in years past, when you'd look at a comic book of Spider-Man, you know, he transformed because he was bitten by a radioactive spider. Well, in the year 2000, even the comic books switched to that being a genetically engineered spider. So there's something about genetic engineering that the public's trying to

think through. Where are we going in the future? And where is this going to take us? It's something small, it's hard to understand, and it's powerful. That's science versus GMOs. This episode has been produced by Shruti Ravindran, Heather Rogers and me. Our senior producer is Caitlin Sori, production assistance by Ben Kebrick. Our editor is Annie Rose Strasser. Fact-checking by Production assistance by Ben Kebrick. Our editor is Annie Rose Strasser. Fact-checking by Michelle Harris and Ben Kebrick.

Music production, mixing and original scoring by Bobby Lord. Thanks to Professor Elizabeth Ransom, Professor Stephen Long, Stephen Tindale, Dr Chuck Benbrook and Joseph Lavelle-Wilson. To hear more of those amazing songs about genetic modification, head to our website, sciencevs.show, or have a look at this episode's show notes. We put links to some of our favourites there.

We're taking a very short one-week break, and when we get back, we're looking at science versus abortion. What exactly happens during an abortion, and what are the real risks involved? Mostly what comes out is something that looks like a tiny cotton ball, kind of a whitish, fluffy tissue. Then that's the placenta and the amniotic sac. I'm Wendy Zuckerman.

Fact you next time.