I'll be giving my interpretation of the UK FSA report into organics and nutrition in two postings here. However I'm not in a position to put the second part up until next week.
The recent report comparing nutritional levels of organic and conventional food excluded 2/3 of all relevant peer reviewed research from its findings.
The report claims to be the most comprehensive study into this subject ever conducted, examining every relevant publication from 1958 to 2008.
However, through a controversial selection process, most publications, including every single publication before 1990, were considered below the authors' quality standard.
Pre-1990 publications were omitted because no organic certification body was listed or inferred in the relevant journal articles, as organic certification was then in its infancy.
Slightly bizarrely, the exclusion of pre 1990 publications was obscured by an unfortunate typo on page 15 of the report. This typo resulted in half a paragraph being omitted from the report, a fact acknowledged in correspondence with lead author Dr. Alan Dangour.
Here, precisely, is what he said to me what I spotted this typo:
BEGINS
Thank you for spotting this. Not sure how it happened as it is not in my final version of the report. The second half of that paragraph should read:
Finally, more than half the studies in the review (54%) failed to provide a clear definition of the organic production methods used (we required a statement of certifying body, although if no certifying body was named it was inferred when possible from the text provided). No study published pre-1990 met this final quality criterion, largely due to the general lack of certifying bodies at that time, although even recent studies often failed to state the name of the organic production certifying body. In total, one third of studies included in the review (34%) met the pre-defined quality criteria (see Table 1).
ENDS
While a careful examination of the publications lists in the appendices would reveal this to the intrepid scholar, the vast majority of readers would have lost this fact.
The study was carried out by the London School of Hygiene and Tropical Medicine (LSHTM) for the UK's Food Standards Agency.
The LSHTM�s team of researchers, led by Dr. Alan Dangour, claims to have reviewed all papers published over the past 50 years that studied nutrient content and health differences between organic and conventional food.
According to Dangor �our review indicates that there is currently no evidence to support the selection of organically over conventionally produced foods on the basis of nutritional superiority.�
To date, many of the criticisms of the report have been well aired. It: rejected publications with foreign language abstracts (i.e. summaries); excluded areas of health concern such as biocide residues and additives; left out important nutritients, downplayed its own significant findings where they suggested organic is superior nutritionally.
For the latter, this includes the findings with regard to polyunsaturated fats in dairy and and meat products.
Indeed, the mean differences revealed in the report do point to the following higher levels in organic food: Protein 12.7%; Beta-carotene 53.6% Flavonoids 38.4%; Copper 8.3%; Magnesium 7.1%; Phosphorous 6%; Potassium 2.5%; Sodium 8.7%; Sulphur 10.5%; Zinc 11.3%; Phenolic compounds 13.2%.
When I put this to Alan Dangor, he replied �It is important to distinguish between "mean differences" and "statistically significant differences".�
However many consumers would be pleased to hear of almost 40% more Flavonoids, over 50% more beta-carotene, and indeed any extra zinc and magnesium.
One of the underreported problems with the report is the fact that individual foods are not considered. Instead, every product within the broad categories of livestock and crops are considered together.
So if, as recent research suggests, organic tomatoes and kiwis are superior nutritionally, this is balanced out by the overall grouping of all fruits and vegetables into one category.
According to the report itself:�The authors understand that combining all crops and all animal products into single groups and analysing the results by nutrient category may have obscured possible nutrient differences within specific foodstuffs. Certain types of foodstuffs may be more
responsive to organic or conventional production systems than others, and these
differences may have been diluted or lost when all foodstuffs were combined in this
manner�.
Considering Dr. Dangor's statement above on mean vs significant differences, this is ironic to say the least.
However leaving out 2/3 of all the relevant research is surely the most glaring issue.
162 publications were identified. Only 1/3, or 55 of these, were considered as at the authors' pre-defined quality criteria.
Yet all of the 2/3 considered below the quality level were actually accepted for publication in peer-reviewed journals.
In other words, the scientific community examined them and found them to be up to the required level for publication in a scientific journal.
So the authors of this report have peer reviewed the peer reviewing process, and rejected 2/3 of what others in the scientific community accepted.
This is especially significant because it is in the 2/3 of peer reviewed publications the authors reject, that the majority of positive research into organic food's nutritional levels is found.
Next posting on this will further examine the rejection of 2/3 of all relevant publications.
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