More companies are rolling out carbon dioxide emission labels on products to help us make greener choices. Unilever, the global consumer goods giant, recently announced it is committing to put carbon footprint information on 70,000 products, while multi-national companies Oatly and Quorn have already started adding labels like this to their packaging.

But this is not the first time companies have tried this. In the 2000s, for example, an international supermarket put carbon labels on hundreds of products, but cancelled the project after a few years.

Why are carbon labels coming back now, and what does this information really tell us? How do you measure the carbon footprint of a product? And will this drive behaviour change and help the environment?

Presenters: Neal Razzell and Graihagh Jackson
Producer: Darin Graham
Researchers: Zoe Gelber and Olivia Noon