London (3.7.07) – Lobbyists for organic practices and products oppose agricultural biotechnology because, they say, GM pollen might “contaminate” their own pristine plantations. That would apparently render them essentially worthless for no discernible reason other than that they say so. To the less dedicated, such protests against GM appear rather to have the hallmarks of brand protection and a determination to preserve market share.

Organic apologists are loud in claiming that their practices and their products are the best in every conceivable way but they find it difficult to garner much evidence in support. This paper looks at just one aspect of trying to making comparisons between “organic” and other foods.

Which is which?

Recent months have seen a number of articles offering claims about the nutritional and health values of organic versus conventionally-produced food (1,2),

Such comparisons are difficult to make. Obviously, one can look only at one or a few foods at a time: there is no way of comparing organic foods as a whole with all their conventional counterparts.

But even with a particular food it is tricky. For instance, there are many different sorts of tomatoes; it would not be valid to compare an organic example of one sort with a conventional example of another. To make the intended comparison everything must be the same except the method of production: organic versus conventional.

Even if one were to compare in that way it would be only of one strain of tomatoes cultivated in a particular organic regime versus the same strain in an equally specific conventional mode. The comparison would have to be repeated for every kind (or variety or type) of tomatoes, all of which would tell you nothing at all about pears or lettuce.

A recent study, readily available on the internet (3), does compare tomatoes – four large fruit varieties and one cherry cultivar grown organically and conventionally in Poland; the precise locations of the farms are given.

But hang on a minute: the farms were 60 km apart and we are given no indication of possible climatic variations between them. Moreover, the organic tomatoes were grown in a light loamy, sandy soil, the conventional ones on heavy clay. So not only might they differ by virtue of production methods (organic versus conventional) but they are 40 miles part and on different soils. Is the comparison one of production method or is it one of micro-climate or is it one of soil or…. ?

Chemical analyses of organic and conventional tomato fruits showed differences in the content of dry matter as well as some other properties: sugar concentration and acidity were two of them, with some of the variations very small. Some tomatoes had more vitamin C than others under both conditions of cultivation. These kinds of differences are often observed when the crop from one field is compared to another using any type of cultivation; moreover, some studies show that annual variations of weather make more of a difference than organic versus conventional farming methods.

The authors concluded that their results “support the GDBH (“growth-differentiation balance hypothesis”) theory as the organic production system, with its lower nitrogen availability in soil, appears to have an impact on the levels of several bioactive compounds in tomato fruit". They go on to say that both organic and conventional cherry tomatoes can be recommended as part of a healthy diet. Fair enough: you could say the same about steak.

When you get right down to it, the paper entitled “Comparison of the nutritive quality of tomato fruits from organic and conventional production in Poland” shows virtually nothing. If, and it is a big if, there is actually any nutritional advantage from the organic varieties you are likely to have to pay a pound more for a penn’orth of dubious extra value. Read the study carefully and ask yourself if those doubtful claimed nutritional benefits are worth it or you could do something better with your money.

That’s the problem. Making the comparison is tricky enough; deciding its significance is an added difficulty. If you like the taste of some particular organic product (or all of them for that matter) and the price doesn’t worry you, then buy. But be advised that, in double blind studies, consumers cannot distinguish between comparable conventional and organic products. So if it is value for money you are after, it might be wise to think again.

David Miliband, the Secretary of State for the Environment, said recently “There is no evidence organic food is better for you than conventional food”; organic food was more of a “lifestyle choice that people can make" (4). He echoes almost exactly the words in September 2000 of Sir John Krebs, the first chairman of the Food Standards Agency: “Organic food is no safer or more nutritious than conventionally grown food” (5).

Sources:

1. So, is organic food really better? The Times (2.4.07) (http://www.timesonline.co.uk/tol/life_and_style/food_and_drink/article1599009.ece)

2. Ian Herbert. It's not just a fad - organic food is better for you, say scientists. The Independent (3.4.07) (http://www.independent.co.uk/environment/lifestyle/article2414745.ece)

3. E. Hallimann and E. Rembialkowska (March 20-23, 2007). Comparison of the nutritive quality of tomato fruits from organic and conventional production in Poland. In "Improving the sustainability in organic and low input food production systems", page 131. University of Hohenheim, Germany: download from https://www.fibl.org/english/shop/show.php?sprache=EN&art=1455

4. 'No proof' organic food is better. BBC News (7.1.2007) (http://news.bbc.co.uk/1/hi/uk/6238227.stm)

5. Organic food 'no healthier'. BBC News (1.9.2000) (http://news.bbc.co.uk/1/hi/health/906530.stm)

Written for CropGen by Vivian Moses, Visiting Professor of Biotechnology, King’s College London and Bruce Chassy, Professor of Food Microbiology, University of Illinois at Urbana-Champaign. and reproduced with the permission of the authors.

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