Everybody currently engaged in the livestock industry would need to be retrained for a new career – this could be in agriculture, reforestation or producing bioenergy. Failing to provide career alternatives could lead to mass unemployment and social upheaval, particularly in traditionally rural communities.

Taking livestock like sheep away could actually have a negative impact on biodiversity, as their grazing has helped to shape the land for centuries – so some farmers could be paid to keep animals for environmental purposes.

No more Christmas turkey – losing meat means that we would also lose traditions. Many communities around the world offer gifts of livestock at weddings and celebrations. For Ben Phalan at the University of Cambridge, this is “why efforts to reduce meat consumption have often faltered”.

No meat would lower the chances of coronary heart disease, diabetes, stroke and some cancers – and so save the world 2-3% global gross domestic product in medical bills.

But we would need to replace meat with nutritional substitutes, in particular for the world’s estimated two billion-plus undernourished people. Animal products contain more nutrients per calorie than staples like grains and rice.

So, have you been tempted to convert to vegetarianism? Why? Let us know on Twitter or Facebook where you can join the conversation with 800,000 Future fans.

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