What are genetically modified foods and why are they controversial?

What are genetically modified foods?

Genetically modified foods, often described as GM foods for short, are organisms that have had their DNA altered in a way that wouldn’t have happened if left to nature. Plants or animals can have specific genes added to them, ensuring that new kinds of organisms are created with properties that the originals did not possess.

Why would you want to genetically modify foods?

There are all kinds of reasons you’d want to modify a species of organism – some economic, some philanthropic and others commercial.

Taking those in order, the first is that a genetically modified crop can be cheaper – in the long run – to produce. This could be because it requires less attention, and therefore less man-hours, or simply because it’s hardier and less likely to die.

The second is related to that. Nobody denies we have enough food for everyone, but there are all kinds of political and technical reasons why it isn’t evenly distributed – and that’s a big humanitarian problem. While it would be nice to imagine a fairer society where we’re better at distribution, that seems like something of a pipe dream. GM crops potentially allow for a far greater yield, and thus more to go around. The United Nations estimates we’ll need to grow 70% more food by 2050 to feed our growing population, so that’s a seriously strong selling point.

That’s not where the good causes end, incidentally: indeed, scientists have recently been working on a kind of rice that produces 90% less greenhouse gas, while producing 50% more rice. This would be a huge help in the fight against climate change. And Golden Rice – a kind of rice with the Vitamin A-producing gene from carrots – was designed to tackle vitamin deficiency that causes millions of people in the developing world to go blind.

Finally there’s commercial concerns. This could be modifying a plant to taste better, but it could also be inserting a gene to make a vegetable resistant against diseases or insect blight, ensuring that less crops go to waste, and there’s more to sell.

Why are people opposed to genetically modified foods?

A number of reasons, again. These can be loosely divided into scepticism of vested interests in scientific research, political worries, concern for long-term side effects, and good old-fashioned media scare stories.

If you’re of a certain age, you’ll probably remember the discourse on GM from the 1990s where there were fears of playing God and creating “Frankenfoods”. As time has gone on, more research has been done and GM foods have been consumed in large quantities, so concerns over the short-term consequences have diminished somewhat.

Which brings me onto the second point: the fear of long-term effects. Critics argue that no matter how many trials have been carried out, by their very nature these can only look at the short-term impacts. They point to the likes of the pesticide DDT that was once declared safe, only to be found as carcinogenic years later. We’re in a different age now, but the point stands: scientists aren’t always infallible, and sceptics make a fair point when they say that tampering with the food supply is a big-stakes game.

Then there’s the concern of vested-interests involvement. Studies funded by those who want to sell more of their products could incentivise scientists to play down side effects and potentially negative findings. More on this later.

I’ll come back to political worries at a later date, but in short – can a specific gene of a crop be copyrighted, thus causing legal headaches for farmers?

But hasn’t genetic modification been going on for years in the form of selective breeding and mutagenesis?

This is true. Selective breeding of crops has been occurring for millennia, and mutagenics – scrambling DNA with chemicals and radiation – has been used since the 1930s. We enjoy the benefits in plenty of the food we eat, including wheat, rice and peanuts, with next to no public outcry.

As Scientific American points out, the difference here – other than media interest – could be that GM methods involve the transfer of a single gene, rather than entire selections, but scientists broadly agree that this is a positive thing. “We know where the gene goes and can measure the activity of every single gene around it,” plant molecular biologist Dr Robert Goldberg told Scientific American. “We can show exactly which changes occur and which don’t.”

What foods have been genetically modified?

Quite a few foods have been genetically modified in one way or another, by far the most widespread being corn and soy. As of 2010, about 90% of the corn produced in the US was genetically modified, chiefly in order to express a protein that kills certain insects. GM soy is even more widespread, with 94% of soybean coverage in the US modified to be glyphosate-tolerant as of 2015. In the US, domestic sugar and vegetable oil are generally genetically modified in some way or other too. Worldwide, a number of fruit and vegetables – including papayas, pineapples and potatoes – have been created.

However, to date, just one food has been approved for growth within the EU – MON 810, a maize that fights off pests – so if you’re in the UK, then you probably haven’t directly consumed as many GM foods as someone in America.

That is about to change. In January 2015, the EU passed a law allowing member states to grow any crops approved by the European Food Safety Authority. Member states can opt out of the legislation if they wish, as Scotland has chosen to do, but they have to inform the EU of their decision by October 2015. So far, it looks like 16, including Germany, Italy, Denmark, Bulgaria and Cyprus, will do so.

However, animal feed is often imported, and farmers are finding it harder and harder to know which feed is GM and which is not.

Could that mean modified genes transfer to humans through the food chain?

Scientific American describes this as “theoretically possible, but hugely improbable,” as genetic material has not been found to survive the tough environment of the human gut to make its way into cells.

Even if it were possible, the genes planted into GM foods are already often consumed by humans as part of natural pesticides in organic farming, so this really isn’t worth worrying about.

What do scientists have to say about genetically modified foods?

Part of the problem with scientific research is that you can’t really ever prove something is safe – you can only fail to find problems. For some reason, people are less concerned with this truth in medicine than they are with GM foods.

Despite this, the research largely points in one direction. Skeptical Raptor has compiled a list of 114 peer-reviewed articles, none of which were sponsored by corporations with vested interests, and each one followed the consensus that GM foods are safe.  

Elsewhere, a metareview has analysed ten years’ worth of GM crop-safety research papers and discovered much the same thing: “The scientific research conducted so far has not detected any significant hazards directly connected with the use of genetically engineered crops.”

This backs up the conclusions of the American Association for the Advancement of Science’s, which aren’t the slightest bit ambiguous:

“The science is quite clear: crop improvement by the modern molecular techniques of biotechnology is safe … The World Health Organization, the American Medical Association, the US National Academy of Sciences, the British Royal Society, and every other respected organisation that has examined the evidence has come to the same conclusion: consuming foods containing ingredients derived from GM crops is no riskier than consuming the same foods containing ingredients from crop plants modified by conventional plant improvement techniques.”

Additionally, while there are a handful of anecdotal stories online about livestock becoming sick after being fed on GM-only diets, a 2014 study assessed over 100 billion animals calls this into question. Analysing the data from before 1996 (when no animals were fed GM) to modern times, they found no trends to indicate any difference in animal health.

By contrast, there are relatively few studies suggesting any side effects from GM foods, and the high-profile ones have tended to be thrown out reasonably quickly. A 1998 study from Árpád Pusztai found that rats fed a genetically modified potato experienced stunted growth and changes to their immune systems. However, it later emerged that the potato was designed to be harmful in order to be used in studies.

Likewise, Gilles-Éric Séralini from the University of Caen found that rats eating a type of GM corn developed high rates of cancer, but his study was widely dismissed over a number of concerns including the breed of rat (which has a propensity for tumours), the number of rats and a lack of proper control groups. The European Food Safety Authority ended up dismissing the studies.

Relative to the body of pro or neutral GM research, these studies are few and far between, but are often latched upon by anti-GM campaigners as being more legitimate precisely because they break with the scientific consensus, which is often accused of being tainted by big business.

Can you trust the researchers?

Many of the complaints regarding the pro-GM research is that much of it is funded by clearly vested interests – agricultural firm Monsanto in particular. The suspicion is that the scientific research can’t be legitimate if the funding is coming from companies that rely on positive spin for their products.

However, even if you discount research that has been funded by outside interests and look purely at independent studies, the recommendations point one way: there are no known dangers to consuming GM foods.

The “known” bit there may sound like a worrying caveat, but as I mentioned above, proving anything isn’t dangerous is virtually unheard of in science. The European Commission has funded over 100 research projects carried out by more than 500 independent teams, and found no reason for concern.

Which countries allow the growth of GM foods?

As mentioned above, the US is one of the largest producers of GM crops, although a handful of Californian counties (Mendocino, Trinity and Marin) have their own bans in place. It’s mainly corn, canola and soy. Canada is similar, as is the majority of South America.

In Asia, China is another massive producer of GM crops, as is India – although that has proved controversial due to reports of widespread suicides of farmers unable to meet the costs of GM seed growth. Japan is staunchly against the growth of GM crops, but imports significant amounts of genetically modified canola.

The European Union is slightly tougher to summarise. The EU has allowed the cultivation of a number of crops, but it’s down to specific member states to decide whether they opt out. England is in favour, while Scotland has opted out. Spain has grown GM maize for many years, while France has an outright ban on all things GM. 

Member states are required to opt out of GM crops by October 2015 and, to date, 14 of the 28 have done so. They are: Latvia, Greece, France, Croatia, Austria, Hungary, the Netherlands, Poland, Lithuania, Bulgaria, Cyprus, Italy, Denmark and Germany. A further two countries have requested partial opt-outs: the UK (for the devolved nations of Scotland, Wales and Northern Ireland) and Belgium (for the French-speaking Wallonia region).

Australia used to have widespread bans on GM crops across their states, but they have been gradually lifting them over time, leaving only South Australia with an outright ban in place.

Images: Uwe Potthoff, William Murphy, Department of Agriculture, Right2Know March, GMO free conference, Jan Smith and George Groutas used under Creative Commons