Is GM food safe?

The short answer is yes.

The slightly longer answer…

A paper has just been published in the Critical Reviews in Biotechnology journal cataloguing and summarising 1783 scientific studies that looked into the safety and environmental impact of GM food. Its conclusion was that

The scientific research conducted so far has not detected any significant hazards directly connected with the use of GE crops

In addition, there is a consensus conclusion from science organisations worldwide, that GM foods are safe. So why then is there such apparent controversy about the topic?

A search of just one online newspaper, the Daily Mail, reveals hundreds of articles about GM food. Many of these question their safety or environmental impact. To get a flavour of the concerns raised by journalists about this issue, I will analyse the first article I clicked on.

ImageThe title of this article ‘‘Frankenstein food’ a good thing? It’s all great GM lies‘ is unashamedly provocative and immediately tells us the stance the journalist is going to be taking. The thrust of the article relate to comments made by Environment Secretary Owen Paterson about whether meat being sold in the UK has been raised on a GM diet. I will however jump forward to focus on the claims made by the article about GM food safety.

The biggest piece of evidence against the safety of GM foods used by the article comes in the form of a scientific study by Dr Spiroux de Vendômois et al in the International Journal of Biological Sciences. Whilst the study in questions concludes that it identified new side effects related to the consumption of GM food, it also has many problems. Chiefly among these is a small sample size. As admitted in the paper

Only 10 rats were measured per group for blood and urine parameters and served as the basis for the major statistical analyses conducted.

When statistical analyses is based upon such a small sample size, it is very difficult to determine what is causing the effects that you are seeing in the data.

The Daily Mail article references a number of other pieces of evidence to further support it claim. It talks about “large-scale GM crop trials conducted in this country”. Without further details or references to this however, I was unable to investigate this.  Other unreferenced claims about studies are also made. The journalist also uses a second hand anecdote to further make her point.

That might explain some anecdotal evidence I came across recently concerning a Danish farmer whose pig herd had mysteriously fallen ill.

Finally, the article cites public opinion in its argument against the proliferation of GM foods in the UK.

a British Science Association survey showed public support for GM crops declining from 46 per cent in 2002 to just 27 per cent now

Of course, it is very easy to cherry pick numbers from two particular years of a survey (and from one of the many questions that was asked) to make your point. I might equally say (using that very same survey) that 25% Britons are now unconcerned by GM food, compared with 17% in 2003. The caution with which we should approach these figures is emphasised by Dr Tom MacMillan, director of innovation at the Soil Association.

The share saying they agree that GM food “should be encouraged” actually drops from 46% in 2002 to 27% in 2012. Not only does that directly call into question the notion that there is greater public appetite for GM, but the fact that the figures are 35% in 2005 yet 44% in 2010 suggest it is absolute nonsense to suggest a clear trend here.

In summery, there is a significant amount of evidence saying that GM foods are both safe to eat and safe to the environment, There still however remains, particularly in the media, the perception, that GM food is unsafe or that the evidence of its safety is not sufficient. Articles claiming such, like the Daily Mail article presented here, point towards single specific studies (which in this case had significant methodological flaws) for support, whilst ignoring the large body of reputable evidence available. In addition, anecdotal evidence and specially selected survey results are used as to support a particular claim.

When trying to sell a certain story or viewpoint, it is of course easy to find a particular study, anecdote or statistic that appears to back you up. Science however does not work like that. Science requires continuous questioning, testing and experimentation in order to come to (and maintain) a consensus conclusion. That is exactly why we can now say that GM food is safe.