Supermarkets have the data to help shoppers eat healthily – but will they listen?

Imagine if the checkout operator at your local supermarket took one look at your basket and turned to you with the following helpful advice: “Do you realise that if you chose an alternative option you could save nearly 500 calories? That’s the equivalent of a 50 minute run!”

It is not hard to imagine what would follow. The sight of oversized shoppers making a (relatively) quick dash for the exit and vowing never to return.

Yet with the huge power of data at the disposal of retailers, in many ways this is exactly what the NHS and public health bosses are crying out for in the war on obesity.

In fact, many experts believe public health measures that rely on voluntary reformulation and portion control are doomed to fail unless supermarkets start actively favouring products that are less calorific.

With PHE due to launch new targets next year for calorie reduction, across a whole raft of products including crisps, ready meals and sandwiches, it is going to need all the help it can get from supermarkets.

But if anyone needed convincing of the potential problems of giving it straight to customers, just see the backlash Ocado has been receiving regarding just such a scheme. Earlier this year, Ocado added a calorie counter to its online checkouts, which not only flags up lower-calorie options for consumers to swap to but brings to life exactly how hard it would be to shift those calories through physical exercise.

Take a certain brand of full-fat coconut milk, for example. When consumers include it in their basket, Ocado points out that the full-fat version contains nearly 900 kcals, while a lighter version is available at less than 550.

That, it explains, is the equivalent of a two-and-a-quarter-hour walk or a 47-minute run.

While health campaigners will argue that no amount of running can outdo a bad diet, it’s a pretty powerful message. And after all, it’s easier to be rude to someone in a computer message – or an online checkout – than face to face, isn’t it?

Well, some Ocado users have taken less than kindly to the revolutionary new feature. “Is this @Ocado calling me fat?,” protested one consumer on Twitter, whose views were echoed by many others. “Ocado, showing alternatives to save me money on my items, great,” tweeted another. “Showing me alternatives to ‘save on calories’. Are you after a fight?”

Others have expressed anger that the health advice is not an opt-in feature, after Ocado replied to angry consumers telling them how they could, if they wanted, choose to opt out of the service.

“Only just started shopping with @Ocado. Nudging me to purchase fewer calories at checkout!” was one response on social media. This sort of reaction might seem a bit precious, but it’s just why retailers have been so cautious about prescribing diet advice to consumers whenever it’s been suggested by public health bosses.

Ocado is not the only retailer trying to nudge consumers to make healthier choices. In May, Tesco used its ‘power aisles’ to encourage shoppers to ditch high fat, salt and sugar products in favour of healthier options, in what it billed as a partnership with suppliers in the fight against obesity.

Yet while this featured healthier alternatives from brands such as Coca-Cola, Irn-Bru, Kellogg’s Frosties, Heinz Salad Cream, Hellmann’s mayonnaise, KP nuts and Ritz Crackers – all with a lower price point – Tesco also slashed the price of the HFSS products at the same time.

While this was perhaps a concession to brands who will fight tooth and nail against being branded unhealthy, Ocado’s calorie-counting experience shows that consumers don’t always like to be told either. Even if the advice could tip the scales towards avoiding those 50-minute runs, or ultimately a faster trip to the mortuary.