The issue of carbon labelling generated heated debate at The Grocer's Sustainability Forum on Wednesday, with Tesco's David North forcefully putting the case for the defence.

There's no doubt suppliers should be encouraged to calculate the carbon footprint of their products, if only to identify inefficiencies in their supply chain.

But does this really need to be on a label? North says the more information you give the consumer the better, yet there is no evidence labelling drives consumers to make better choices. Indeed, a study last year showed consumers actually bought fewer healthy ready meals after traffic-light labels were added.

By adding carbon to the mix you create a paradox for the shopper. Do you choose the healthier product or the lower-carbon product? And what of water? If water security is such a big deal should we not splash a water label across our food and drink?

Consumers have enough choices to make without weighing up their own health against that of the planet. Suppliers should do the work for them, because by the time the product reaches the shelf, less information is almost always more.