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[SANET-MG] organic tomatoes are healthier
The debate over organic tomatoes continues. It reminds me of a comment
form the editor of the British Food Journal who noted that there is a
common misconception that science is about facts. The comment from Lord
Krebs , principal of Jesus College Oxford and member of the house of
lords , both appointments suggests that the Lord is providing divine
revelations. However, Lord Krebs is well known as a Bird Brain who has
little knowledge outside of Bird behavior. His opinion that high
flavonoids are not healthy nutrients are like proclaiming the world to
be the center of the known universe. The views of Claire Williamson from
the British Nutrition Foundation are typical of her report which
compiles only that evidence which supports her views . The evidence that
organic tomatoes are healthier stands and obfuscation from enemies of
organic foods has not detracted from that evidence.
Breaking News on Supplements & Nutrition - Europe
Are organic tomatoes more nutritious?
By Stephen Daniells
05/07/2007- Organically grown tomatoes contain higher levels of
beneficial flavonoids, says a new study from the US that fans the flames
of the debate between conventional and organic foods.
The new study, published in the Journal of Agricultural and Food
Chemistry, reports that tomatoes grown organically contained higher
levels of quercetin and kaempferol aglycones than their conventionally
According to a study published recently in the Journal of the Science of
Food and Agriculture, the world market for certified organic foods was
estimated at $23-25 bn (€17.3-18.8 bn) in 2003 with annual growth of
about 19 per cent.
Alyson Mitchell from the University of California-Davis, and researchers
from University of Minnesota studied the levels of quercetin and
kaempferol aglycones in dried tomato samples (Lycopersicon esculentum L.
cv. Halley 3155) between 1994 and 2004. The tomatoes were grown and
processed conventionally or organically.
Mitchell and co-workers report that organic tomatoes contained on
average 79 and 97 per cent more quercetin and kaempferol aglycones than
conventionally grown tomatoes.
The explanation for these observations was that 'over-fertilisation' of
the conventionally grown plants. Flavonoids are produced as a defence
mechanism of the plant in response to nutrient deficiency. In the
organically grown plants, no fertilisation occurred which was mirrored
in increasing levels of the flavonoids over time as the soil fertility
"This increase corresponds not only with increasing amounts of soil
organic matter accumulating in organic plots but also with reduced
manure application rates once soils in the organic systems had reached
equilibrium levels of organic matter," concluded the researchers.
Commenting independently on the research, Lord Krebs, former chairman of
the UK's Food Standards Agency (FSA) and now an academic at Oxford, told
The Times that higher flavonoid levels do not necessarily mean that
organic food is healthier.
"This depends on the relevance of the differences to the human body.
Tomato ketchup has higher levels of lycopene [a strong antioxidant] than
either organic or conventional tomatoes. So if you wanted lots of
lycopene you should eat tomato ketchup," he said.
A recent review, published in the journal Nutrition Bulletin and
authored by Claire Williamson from the British Nutrition Foundation,
stated that the overall body of science does not support the view that
organic food is more nutritious than conventionally grown food.
"Organic farming represents a sustainable method of agriculture that
avoids the use of artificial fertilisers and pesticides and makes use of
crop rotation and good animal husbandry to control pests and diseases,"
wrote Williamson. "From a nutritional perspective, there is currently
not enough evidence to recommend organic foods over conventionally
Source: Journal of Agricultural and Food Chemistry
Published on-line ahead of print, ASAP Article doi: 10.1021/jf070344+
"Ten-Year Comparison of the Influence of Organic and Conventional Crop
Management Practices on the Content of Flavonoids in Tomatoes"
Authors: A.E. Mitchell, Y.-J. Hong, E. Koh, D.M. Barrett, D. E. Bryant,
R.F. Denison, and S. Kaffka
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