The researchers examined the nutritional contents of carrots, onions and potatoes grown under both regimes and in particular, they looked at the concentrations of polyphenol antioxidant compounds such as flavonoids and phenolic acids- compounds which are believed to reduce the risk of dementia, cardiovascular disease and some cancers.
The results of the study, published in The Journal of Agricultural and Food Chemistry show that in onions and carrots, there was no difference in the amount of these compounds between conventionally and organically grown crops; while in potatoes there was a small increase in organically grown potatoes.
The researchers point out that the slight increase in the potato samples may be due to these plants being grown on a different farm.
As reported in an interview in this morning's Irish Examiner, Grace Maher of the Irish Organic Farmers and Growers Association claimed that this was "an isolated study" and that their research showed that people bought organic because "it is free from pesticides, free from GM materials...we also believe that organic food is more nutritious."
Despite what people might "believe", the evidence that organic food is no more nutritious has been shown previously.
A study in July 2009 by the UK Food Standards Agency showed that there was no significant differences in nutrition between organic and conventionally grown plants. So, the idea that this is an "isolated study" is incorrect.
The incorrect assumption that organically-grown produce tastes better than other foods has also been disproved by a team of Irish researchers.
As reported on this blog earlier this year, scientists based in Dublin Institute of Technology have shown that a panel of consumer tasters could find no significant difference between organic and non-organic potatoes.
As I've pointed out here in the past, while there may be some environmental benefits in "going organic" the effect on the food itself and on consumer health seems to be in some dispute.