Mars UK tried to curry favour with health chiefs by halting production of its super-size chocolate bars to help to tackle obesity.

But, instead of shrinking its bars, the confectionery giant has simply split them in two, selling both parts inside one wrapper.

Mars Duo may look slender in its longer pack, but the product still weighs 85 grams (3oz) and contains 386 calories – exactly the same as the criticised king-sized bars.

Similarly, Snickers Duo is sold as two bars. But the product weighs 100 grams and, with 511 calories, has exactly the same calorific content as the former king-size bar.

Health campaigners are now accusing the manufacturer of cynicism and are questioning the company’s commitment to improving the nation’s diet.

The Snickers Duo was singled out by MPs on the Commons Health Committee for contributing to rising levels of obesity. Its calorific content is a quarter of a woman’s daily recommended requirement and, MPs were told, it “contains more calories than a meal of sirloin steak, potatoes and broccoli”.

The issue is timely. This week the Food Standards Agency ends its consultation on how to encourage healthier eating and to reduce saturated fat content in foods.

The need for smaller portions in chocolate, crisps and other snacks is one of the key proposals in the agency’s plan to improve the nation’s diet.

Small chocolate bars are usually available only inside super-market multi-packs. But the agency wants to see more chocolate bars on sale with fewer than 100 calories.

The Mars and Snickers Duos are marketed for sharing or saving for later. They include step-by-step picture instructions on how to open the Duo into two bars.

Campaigners, however, are not convinced. “I know the manufacturers say eat one and save it for later, well I’m sorry, but you just never see children doing that. Once the wrapping is open the bar is eaten,” said Susan Jebb, head of obesity research at the Medical Research Centre in Cambridge.

She added: “I have always been concerned about super-size confectionery and therefore I think it is a small step to split a chocolate bar in two.

“It is more overtly a bar for sharing. But my worry is that most people will still eat both bars. I would suggest that if someone does wish to eat that amount they should buy two separate smaller bars. They may then think twice about opening the second wrapper.”

Richard Watts, food campaigner at Sustain, which has been prominent in the fight to ban junk food television advertising to children, said: “It is a cynical ploy and yet more evidence that we have to take industry’s promise of good behaviour with a pinch of salt.”

Sue Davies, the chief policy advertiser at Which?, the consumer organisation, said that a Duo was better than a super-size bar because it suggested sharing.

“I do think that once someone starts eating a Duo they will finish both bars. But they are being made to think about it, which is a good thing,” she said.

A spokesman for Mars UK said: “Our Mars and Snickers Duo products have been designed so that they are available in two pieces.

“This encourages people to share them or eat them on separate occasions.”

Obesity rates have tripled in Britain in the last 20 years, with almost a quarter of adults now classed as obese. In England more than 300,000 deaths a year are caused by obesity and associated health problems cost the NHS £1 billion a year.

Weighting list

492

calories in a 215g Big Mac

294

calories in a 65g Mars bar

212

calories in a packet of 40g Wotsits

182

calories in a pint of beer

94

calories in a 24g Special K bar

139

calories in a 33cl can of Coca-Cola

64

calories in a 25g rasher of bacon

Source: weightlossresources.co.uk

300,000

deaths a year In England caused by obesity

Source: Times database

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