The quantity of cereals harvested in the world has trebled in 40
years [correction: nearly trebled in 50 years!], but the acreage
planted to cereals has hardly changed at all.
(graph from my book)
That remarkable achievement is mostly down to the fact that most
farmers now get extra nitrogen straight from the air, via ammonium
factories, rather than from plants, dung and dead fish -- the
If the world was fed with organic food, it follows, we would
need to cultivate or otherwise exploit far, far more land to get
the plants, dung and dead fish to produce the same amount of food.
As I submit to being preached at by organic farmers about their
virtue, this fact keeps creeping into my head. Wholly organic
farming means no rainforests or it means hunger and high food
The organic folk usually reply by saying that their farms are
better for wildlife on a local level. Well, now comes a comprehensive study of British farmland that
says they are not even achieving that:
While there were more plants and
butterflies on organic farms, there was no difference in the number
of bees and there were 30 per cent more hoverflies on conventional
farms. Organic fields contained more magpies and jays but 10 per
cent fewer small birds such as yellowhammers, corn buntings,
linnets, skylarks and lapwings.
(More magpies, fewer songbirds: Duh! Magpies predate songbird
The study (original paper behind a paywall, but abstract here) also confirms that organic farming uses
up more land to produce the same amount of food:
It concludes that organic farms produce
less than half as much food per hectare as ordinary farms and that
the small benefits for certain species from avoiding pesticides and
artificial fertilisers are far outweighed by the need to make land
more productive to feed a growing population.
Last year saw another organic myth laid firmly to rest, when
Alan Dangour did a huge survey of all studies purporting to test
the health benefits of organic food and found:
Our systematic reviews found that there
was no evidence of any important differences in the nutritional
composition of foodstuffs grown using conventional and organic
farming methods. There was also no evidence of nutrition-related
health benefits from consuming organically produced foods.
Bruce Ames long ago (here and here) laid to rest the myth that pesticide
residues in conventional food pose a risk to human health:
The pesticides in our diet are 99.99%
natural, since plants make an enormous variety of toxins against
fungi, insects, and animal predators. Although only 50 of these
natural pesticides have been tested in animal cancer tests, about
half of them are carcinogens. About half of all chemicals tested in
animal cancer tests are positive. The proportion of natural
pesticides positive in animal tests of clastogenicity is also the
same as for synthetic chemicals.
Given that organic farms use crushed fish, flame-throwing weed
control, copper sulphate pesticides, poorly paid labour, and given
that it still it takes just about the same calories of fossil fuels
to get an organic lettuce from a Californian farm to a plate in New
York -- 4,600 versus 4,800 (numbers from Michael Pollan's Omnivore's Dilemma) -- can we please have a
little less preaching of organic's holiness?
By all means eat organic food if you want to. But be honest and
admit that, as far as the health of the planet is concerned, you
are being selfish, rather than virtuous.