The Impact of Pork Products on Climate Change

Unlike cows and sheep, pigs don't emit methane, and they're better than cattle at converting their feed into meat. Pork is still a carbon-intensive food, however, producing around eight times its own weight in CO2. Moreover, of all the widely available meats, this one raises the most press-sing animal welfare questions. Pigs are highly intelligent social animals, comparable to dogs in the IQ stakes, and yet they're often reared with little respect for their wellbeing. Pig farming techniques have become increasingly industrial over the past few decades. Farms are growing to 'epic sizes (in the US, there are now individual farms with more than a million swine) and the sow has been transformed into a meat-making machine. Relatively recently, female pigs would give birth to around five piglets a year, but twenty-five is not uncommon today. This is thanks to a mixture of intensive breeding practices and the technique of removing piglets from their mothers very early, to maximize the number of possible pregnancies per year.

The UK is better in terms of pig welfare than most of Europe, where many pigs still spend their whole lives in sow stalls - barren cages, often so small that the pig can't turn around for an entire pregnancy - or chained to the floor with a tether. Routine "docking" of tails and clipping of teeth is also common in much of Europe, to avoid the pigs biting each other - something they generally do only in cramped conditions with nothing to keep them entertained. Most of these techniques are due to be made illegal across the EU, but not until 2013.

In the UK, things have been improved by various bits of legislation, but the situation is far from rosy. According to Compassion in World Farming fewer than half the pigs in the UK are even provided with straw. This leaves them on bare floors, which can cause health problems as well as preventing normal behavior. Moreover, farrowing crates - small stalls into which sows are put for a week or two either side of giving birth - are still the norm. The industry claims these are needed to protect piglets from being crushed by their mother, but organic farmers have shown that with good husbandry farrowing crates aren't necessary.

When you do buy pork products, favoring British - and preferably local - producers will help reduce the meat's transport emissions as well as ensuring somewhat better animal-welfare standards. Better still, look out for free-range pork. At minimum, you'll know the pigs aren't kept permanently indoors. Note that outdoor-reared is better than outdoor-bred - the latter ensures that the pig was born in free-range conditions (so no farrowing crates), but the former also implies that it was raised outdoors.

Organic pig meat - which is free-range but allows pigs to be kept indoors for a proportion of the time - offers further improvements. Farrowing crates are out; rooting and exercise areas are in; piglets are not removed from their mother so early; the diet is better; and medicines used must be approved by a certifying body.