A Gail’s sandwich contains more salt than an adult should eat in an entire day, according to new research that has reignited calls for tougher rules on food reformulation.

Action on Salt & Sugar, based at Queen Mary University of London, found that Gail’s Smoked Chicken Caesar Club contained 6.88g of salt, exceeding the recommended adult daily maximum of 6g in a single lunch.

The campaign group said the sandwich contained more salt than nearly five McDonald’s cheeseburgers, as well as 1,067 calories, 90 per cent of an adult’s maximum daily saturated fat limit and just 20 per cent of the recommended daily fibre intake.

The findings form part of a wider survey of 546 sandwiches, wraps, rolls and baguettes sold across UK supermarkets and high street food-to-go operators.

More than one in 10 products exceeded government salt targets, while nearly half would receive a red high salt warning on front-of-pack labelling.

A quarter of the sandwiches surveyed were also classed as less healthy under HFSS rules, meaning they face restrictions on how and where they can be promoted.

Action on Salt & Sugar said the Gail’s product highlighted a wider problem across the food-to-go market, where everyday lunch options can contain unexpectedly high levels of hidden salt.

Out-of-home sandwiches were generally found to be saltier than those sold by supermarkets. Other high-salt products included Gail’s Smoked Salmon Bagel with Schmear and Pickled Pink Onions at 4.2g of salt, PAUL’s Rosette Cheese Salami Gherkin at 4.19g, and Pret a Manger’s Ham & Grevé Baguette at 3.85g.

The retail sector was also criticised, with Tesco’s Fully Loaded Hot Honey Halloumi, Falafel and Pickled Slaw containing 3.78g of salt, Tootoomoo’s Sriracha Pork Sando containing 3.67g, and Sainsbury’s Kitchen Deli Pastrami, Cheddar Cheese & Gherkin Mustard Mayo also containing 3.67g.

However, the research found wide differences between similar products, suggesting high salt levels are not unavoidable.

Pret a Manger’s Chicken Salad Sandwich contained 2.22g of salt, while Greggs’ Roast Chicken Salad Sandwich contained 1.1g. M&S’s All Day Breakfast Sandwich contained 2.65g of salt, compared with 1.54g in Sainsbury’s All Day Breakfast Sandwich.

Lower-salt examples included Urban Rajah’s Smashed Onion Bhaji & Chickpea Buroti at 0.7g, Lidl’s Hoisin Duck Wrap at 0.75g and The Gym Kitchen’s Korean BBQ Chicken Wrap at 0.80g.

Action on Salt & Sugar said several businesses had shown that better performance was possible. Every product surveyed from Pollen + Grace, The Gym Kitchen and Urban Rajah met calorie and salt reduction targets, carried no red front-of-pack warning labels and was not classed as HFSS.

Among retailers, Asda and Lidl achieved full compliance with the salt targets for sandwiches. Starbucks and Greggs recorded the lowest average salt levels in the out-of-home sector and met both salt and calorie targets.

The campaign group is calling on ministers to review salt reduction targets, introduce tougher mandatory limits through the government’s Healthy Food Standard, and bring in financial penalties for companies that fail to comply.

Action on Salt & Sugar head of research and impact Sonia Pombo said shoppers were often unaware of how much salt was hidden in convenience food.

“Most people choose sandwiches for lunch for their simplicity, convenience and affordability. But what they’re actually eating can be a full day’s worth of salt hidden between two slices of bread,” she said.

“More than 20 years after the first set of salt reduction targets were introduced, it’s frankly unacceptable that some companies continue to sell sandwiches that exceed an adult’s daily limit in one go.”

British Heart Foundation senior dietitian Dell Stanford said most of the salt people eat is already in the food they buy, making reformulation critical.

“We need Government to step in and incentivise manufacturers to take out excessive amounts of salt in our food,” she said.

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