This is closely followed by poultry, as it takes 7kg of greenhouse gases to produce 1kg of poultry meat.

For red meat fans, the picture is darker still when you take into account its methane production.

Pigs and poultry do not produce methane so they have much lower emissions than red meats, such as beef and lamb.

Which is more harmful, methane or carbon dioxide?

When it comes to emissions, carbon dioxide is often the first gas to be targeted, but methane is a far more potent greenhouse gas.