© TruviaThe Truvia sweetener ad containing the phrases ‘natural deliciousness’ and ‘from nature for sweetness’: British Sugar gave assurances it would not repeat the claims.
The controversy is the latest to surround Truvia, which was developed by Coca-Cola and Cargill and contains extract from the stevia leaf - although this accounts for less than 1% of the finished product.
Cargill, which brought Truvia to the UK through a partnership with British Sugar's retail brand Silver Spoon, has already paid out over $6m (£3.9m) in the US to settle lawsuits alleging it misled shoppers by describing the product as "natural", although it did not admit liability.
However, in May an advertisement was published in the UK describing Truvia as "natural deliciousness" and "from nature for sweetness".
After seeing it in the newspaper, Guardian reader Chris Hughes, from Leicester, lodged a complaint with the Advertising Standards Authority (ASA) and Silver Spoon agreed not to republish the offending claims.
An ASA spokesman said:
"We received a complaint about a press ad by British Sugar plc that promoted Truvia. The complainant challenged whether the claim that the product was 'natural' was misleading and could be substantiated.The fact that the matter was resolved informally meant that the simple fact that a complaint was made against British Sugar/Silver Spoon was registered on the ASA website but no details of it.
"We approached the advertiser with the concerns that had been raised. They gave us an assurance that they would withdraw the ad and not use the claim in their future campaigns for the product. On that basis we closed the case informally."
It is the second time the product has been the subject of an informally resolved ASA case. In April last year, British Sugar/Silver Spoon agreed to withdraw a TV advertisement after a single complaint claiming it misleadingly implied that the Stevia plant was the major constituent of the product and that Truvia was a natural product.
The claims relating to the naturalness or otherwise of Truvia are particularly sensitive as the product's emergence was partly to do with the high chemical content of existing artificial sweeteners such as saccharin and sucralose, and in particular consumer concerns surrounding aspartame.
Following the US settlement, Cargill retained the right to describe Truvia as "natural", albeit with an asterisk inviting customers to seek out more information about how it is made on the product's website.
The plaintiffs had argued that although the product contained stevia leaf, it was chemically processed and the bulking agent erythritol is synthetically made.
Erythritol has also attracted controversy. It was approved for use as a food additive by the US Food and Drug Administration (FDA) in 2001 but last year a study published in Plos One (Public Library of Science) found that it killed fruit flies. Questions have also been raised about the manufacturers' claims that Truvia is not genetically modified.
The Truvia website says the dextrose used to make erythritol "is derived from the starch component of US-grown corn. Both GM corn and non-GM corn are grown in the US today. Cargill does not segregate the corn used to manufacture the dextrose used in the erythritol process".
It says it is labelled non-GMO because "erythritol itself is not derived from a genetically modified source, and does not contain any genetically modified proteins".
Hughes, 67, a retired lorry driver and office worker, said:
"Cargill had to change their US marketing, now they're trying it on in Europe. They've promised the ASA to drop the ad and change their wording, but the ASA hasn't published this information because it's an 'informal resolution'.A Silver Spoon spokesman said:
"Consumers should have better protection. They shouldn't have to rely solely on the vigilance of the press."
"At the time of the complaint the print advertising campaign had come to an end, so we simply decided to not to run this particular advert again. The ASA are happy with our response."
Comment: Any 'natural' product Coca-Cola and Cargill promote is highly suspect!