Almost certainly this is the usual pseudo-scientific bullshit that has become all too common in the field of health research.
Dr John Ray from the Food & Health Skeptic blog comments:
Most amusing: A "healthy" choice turns out to be anything but. I wonder how the "health" establishment will handle that? Sadly, however, this is not as good an example of the limits of official wisdom as it looks.The article is a much better example of how medical researchers tend to work in a sort of vacuum and ignore the big picture. It in fact reveals an extraordinary lack of insight into their own society by these eight New Zealand researchers. It was once illegal to buy margarine without a doctor's prescription in N.Z. They have a big dairy industry that they like to prop up. So, given the peculiarly strong emphasis on margarine as a therapeutic agent in New Zealand, it would seem highly likely that people who felt less healthy to start with tended most to buy it. And people with poor health have less healthy children -- and lower IQ is one correlate of poor health. The findings then tell us about who buys margarine rather than any effect that margarine has. Trans fats indeed! What we see in the report is not the influence of trans fats but the influence of unwarranted assumptions and conventional thinking. It never ceases to amaze me that people who claim to be scientists seem to think they can just intuit the causal relationships in a dataset. They are witchdoctors, not scientists. Not one out of the eight of them said: "Hey! Wait a minute!"The journal abstract is here. The title of the article is "Dietary patterns and intelligence in early and middle childhood" and the leading author is Reremoana F. Theodore. No corresponding author or email address is given, which is rather strange