Ethical shopping can give you a headache. Which are better — the green beans from Kenya that help Third World farmers to earn a living? Or the green beans grown just up the road that haven’t been air-freighted and will, presumably, help local farmers to earn a living? Should you buy organic beans in Tesco (profits now £3 billion a year) or non-organic from your greengrocer?

I don’t know about his profits, but in winter his hands are often too cold to operate the till. Personally, I’ll buy the Kenyan beans from him, not least because I like shopping somewhere they seem pleased to see me.

Clearly, though, the recession has helped many of you to make at least one decision: organic is a luxury you can no longer afford. Sales of organic produce in supermarkets are in freefall — down by 22 per cent in the first quarter of this year. The curtain has fallen on an extraordinary boom: until 2007 organic sales had risen by an average of 26 per cent a year since 1993.

“Buying organic is just snobbish, especially now,” says one house-husband I know. It’s a popular theme. But there is a logic gap here that is particularly evident this week. Organic food is healthier food — and not just on the table. Swine flu is “a genetic chimera probably conceived in the faecal mire of an industrial pigsty”, as one flu expert put it this week.

He was referring to the factories where thousand of pigs are kept in disgusting conditions to satisfy our endless demand for cheap bacon: there is one right next to the village in Mexico where the flu is thought to have first jumped species. Swine flu has been endemic and evolving on American intensive pig farms since 1998, according to New Scientist. Bird flu was widely blamed on industrial poultry production in East Asia.

Clearly, keeping animals packed together in unnatural conditions is conducive to the breeding and mutation of viruses. Most food scares of recent years — dioxin contamination of Irish pork, antibiotics in Scottish salmon, salmonella in chicken, BSE and so on — come down to unnatural, intensive farming practices done on the cheap. Then there is the troubling disappearance of the honey bees, thought to have been caused by pesticide overuse.

Now, I’m not saying that buying organic will save us from swine flu or bring back the bees but, clearly, if you worry about these things you should choose to eat food that has been produced in a natural way, with minimal chemicals and without cruelty to animals.

But organic is so expensive! Well, it is if you are mug enough to buy it from supermarkets, where the mark-up ranges between 20 per cent and 60 per cent. Buy from farmers’ markets or organic box schemes and you should get a better deal.

Riverford Organics, which delivers 40,000 boxes around England every week, compares its produce monthly against its equivalents in Sainsbury’s, Tesco and Waitrose. It claims that its box foods turn out to be at least 20 per cent cheaper (I did a spot check — this week Riverford’s large organic eggs cost £2.05 for six; in Tesco they were £2.13 and in Waitrose £2.24). Riverford’s sales are still increasing, I am told.

Supermarkets now sell more than 70 per cent of organic produce in the UK — but, having done well in the organic boom, they are now bearing the brunt of the decline. According to Soil Association surveys, it is “barcode” sales of organic that are falling: farmers’ markets, farm shops and box schemes are all doing OK.

Chris Walton is a farmer in the Borders, raising and selling organic lamb, pork and beef (the Walton farm was home, until a few weeks ago, to our family pig). He sells directly to restaurants and delis, through farmers’ markets and on the internet. Chris says that business is pretty good. “Our sales are still rising. We’re selling lots of chorizo, salami, cheaper cuts and mutton. I think people are savvier — they are eating at home, and if they have a job they are probably better off because fuel and mortgage costs are down.”

And swine flu? “Our animals live outdoors. They are in closed herds. Organic does generally mean a higher degree of bio-safety.”

Our pig — he rests in peace in the freezer now — was always a picture of happy health. His vet and medicine bill for all his life came to £1. I would willingly have kissed him on the nose.

alex.renton@thetimes.co.uk

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