The scientist who concluded that organic food is no healthier than conventional produce has been bombarded with abusive messages from zealous environmentalists.
Dr Alan Dangour, a nutritionist at the London School of Hygiene and Tropical Medicine, told The Independent that hundreds of people had contacted him since his work was published, accusing him of dishonesty and incompetence in with some emails peppered with swear words.
"A lot of them have been unpleasant reading," said Dr Dangour, whose controversial study found no evidence that organic food was significantly healthier than food produced using chemicals.
"They were saying I'm a quack. I should do something else and stop wasting my time, but also a lot of stuff saying I must have been funded by Monsanto or big industry.
The academic said that, although he not been upset by the hate mail, he had been "taken aback" by the ferocity of the language.
His research, funded by the Food Standards Agency, could hit the £2bn-a-year organic industry in Britain, just as sales are struggling in the recession.
Published in the American Journal of Clinical Nutrition last Wednesday his study - which reviewed 50 years of scientific evidence - has polarised opinion between those for whom it has confirmed long-held suspicions about the organic movement and those who believe it was outrageously one-sided.
In the Daily Mail, food writer Joanna Blythman, branded the study a "cancerous conspiracy".
Dr Dangour, who spent more than a year with a team of nutritionists analysing 162 peer-reviewed studies, said that he had been sent between 250 and 300 emails personally, with hundreds more arriving at the FSA and his university.
Among the more printable comments were: "Shame on you and this bogus so-called study" and "To the quacks who wrote the study and concluded that organic foods have no health benefits over conventional foods: you blokes are freakin' whacky".
While Dr Dangour found the abuse "mildly entertaining", he was surprised at its vehemence.
"I have received an awful lot of emails," he said.
"Half have been positive saying we really needed this; and I have received a lot of negative emails, some of which have been abusive. I'm not sure I expected that; I was quite taken aback. There have been several things that have come up frequently.
"Some have questioned my integrity and independence; whether I am funded by big agriculture or industry. It's professionally hurtful for people to say: 'You must be funded by industry or otherwise you wouldn't have come up with that finding'."
Yesterday John Mackey, head of Whole Foods, caused further unwelcome publicity for the organic movement by suggesting his flagship store in London sold too many fatty treats.
"We sell a bunch of junk," he said adding that there needed to be more health education at his UK division, which lost £36m last year, despite a considerable interest among the public for organic produce.
Nine out of 10 British shoppers buys organic, but debate has long raged about whether it is healthier for individuals as well as better for the environment.
In internet forums, organic supporters have complained that Dr Dangour's study should have looked at the health impact of pesticides, while others pointed out the work did not nullify the environmental benefit of organic farms, which are generally acknowledged to be good for wildlife.
Others said they bought organic food because it tasted better.
The Soil Association, Britain's main organic certification body, pointed out that while all 162 relevant studies reviewed found organic to be higher in many nutrients such as beta-carotene, the review concluded there were no important benefits from only 55 "high quality" studies.
Dr Dangour said the group had been unfair.
"The Soil Association obviously have their own point of view but in certain circumstances the way they tried to make their point has not been entirely appropriate," he said.
"If you pull random numbers from the report and claim that they are significant, that is not helpful."
Peter Melchett, policy director of the Soil Association, disapproved of any personal attacks on any individual.
But, in a sign that the public debate on the topic is unlikely to be quelled any time soon, he labelled the FSA study "bad science". "It's the nature of science that bad science doesn't last," he said.
"And I'm convinced that this is bad science. Over the last weekend a number of scientists around the world have read the papers and the fury that's building against the study from serious and reputable scientists is enormous."
The Soil Association has long suspected that the FSA is anti-organic, a view fuelled by the hostility expressed towards health claims made for organic by the agency's first chairman, Sir John Krebs.
Yesterday the FSA stood by its research, describing it as "the most scientifically rigorous, independent review of research ever carried out in this particular area".
"Opinion has, at times, been rather polarised," it added.
"The FSA is neither pro- nor anti-organic food and recognises that people choose to eat organic for many different reasons."
Dr Dangour insisted: "I'm not pro- or anti-organic. I'm a scientist and I pulled together a leading team of nutritionists for this research. We have done it entirely properly and correctly and it's been peer-reviewed."
He said he would have liked to have included new EU-funded research into organic nutrition by Newcastle University published in April last year, after the February cut-off date for his research period set by the FSA.
Another report from the EU study provisionally finding organic food is healthier is due to be published in an academic journal later this year.
Dr Dangour nonetheless said the evidence was sufficient to come to a judgement about the nutritional content of organic food and said the number of studies was better than for many other meta-analyses.
Professor Anthony Trewavas at Edinburgh University, a long-time critic of organic food, backed him.
"The trouble is that ideologues have propounded the idea that organic must be better for you because simply it's more natural. Nothing really could be further from the truth," he said.
But conclusive proof about the differences between the two farming systems could only come from cohort studies of illnesses over a long period of time n like the 200 studies done to prove the link between diet and cancer n and they were unlikely to be funded," added the professor of plant biochemistry.
"If you are eating the recommended diet of five portions of fruits and vegetables a day that is designed to saturate you in minerals and vitamins, there is no benefit from eating more. The fact is that the five a day from conventional farming is perfectly adequate for our health," he said.
Nutritionists pointed out that, whatever the truth of the organic debate, Britons still ate too few plants. Adults eat an average of 2.7 portions of fresh fruit and vegetables a day.
Helen Tracey, of the British Dietetic Association, said that some studies showed that some organic products, such as milk, were significantly higher in nutrients.
"We don't always recommend organic as better," she added.
"We say it's much better to have a good range of fruit and vegetables that you can afford in your budget."