Polite readers should turn their eyes away from this column and concentrate on what other nice people have written on these pages. The blunt truth is that, for this week only, this is not so much a Fen Blow as a Fen Blow Off. Two years ago, American scien

Polite readers should turn their eyes away from this column and concentrate on what other nice people have written on these pages.

The blunt truth is that, for this week only, this is not so much a Fen Blow as a Fen Blow Off.

Two years ago, American scientists produced a report that showed the average cow produces ten kilos of wind a year (not including burps).

That is, to put it bluntly, ten kilos of farts. When you think about the probable weight of a fart, that must be a huge volume.

As these emissions contain methane, this could mean that even the comparatively few cows in Fenland are seriously responsible for global warming. Maybe they knew the danger back in the 17th century when a law was passed forbidding tenants in Wimblington to keep more than six cows each.

However, no farmer I've consulted in the last week had a clue how you'd collect and measure any particular cow's farts. And even if you did invent a method, how would you know your cow wasn't holding on to them until you'd moved on to another cow?

Now some wonderful scientists living in San Francisco have worked out that humans are also to blame. It is a scientific fact that all humans pass wind.

It has also been proved that most humans blow off about 14 times a day - mostly at night. In doing so, we each produce half-a-litre of gas.

This is where it gets worrying. The more fibre we eat, the more gas we produce. A medic called Dr Levitt made one patient live on entirely high-fibre beans for a week - and the patient increased his gas output ten-fold.

It's also a fact that our gasses contain carbon dioxide and methane, which both damage the environment.

So we can either give up eating fibre, die young and save the planet - or eat fibre, get healthy and destroy the ozone layer.

Incidentally, both carbon dioxide and methane are odourless. Any smell comes from other chemicals present in the human gut - especially hydrogen sulphide and some fatty acids.

Personally, I cherish a quote from the medical pundit Dr John Collee: "Farting should be fun... Breaking wind is a harmless source of enjoyment which we should learn to tolerate and celebrate.