The use of High Fructose Corn Syrup (HFCS) as a sweetening agent in food and drink has become a hot potato in the US. Some scientists blame HFCS for rising obesity levels while others suggest that describing it as 'all natural' is misleading. But Annette Farr argues that making a scapegoat of one type of refined carbohydrate is rather missing the point.

High Fructose Corn Syrup (HFCS) is having a tough time. For some three decades, manufacturers of the corn starch-derived sweetener have been happily supplying food and drink companies with a sweetening agent, nutritionally similar to table sugar, but cheaper to process than sugar cane or sugar beet.

Starch is extracted from corn and then converted by acids or enzymes to glucose. Then some of the glucose is further converted by enzymes into fructose. The end product is a sweet syrup which blends easily with liquids and food ingredients.

In the US, full calorie soft drinks and other beverages, such as ready-to-drink teas, are mostly sweetened with HFCS. In the UK, HFCS is known as glucose fructose syrup and appears in a variety of food and drink products including Ribena and Ocean Spray drinks.

The current furore surrounds that old chestnut, obesity. HFCS is being blamed in the US - even to the extent of being labelled Devil's Candy by some sections of the media - for the country's rising obesity levels.

In a tit-for-tat war of studies and counter studies, evidence has been put forward alleging and disputing a causal relationship between the rise in obesity and increased consumption of HFCS in food and drink. For example, a study from the Pennington Biomedical Research Center at Louisiana State University supports the link, while others, such as that conducted by Dr Marilyn Shorin and published in Nutrition Today, contradict the theory.

Commenting on Dr Shorin's study, Dr Richard Adamson, senior scientific consultant for the American Beverage Association, said: "While critics have attempted to suggest that HFCS is handled differently in the body and plays a prominent role in causing obesity, these recent studies show HFCS is no different than ordinary sugar."

There is further confusion over the use of the words 'all natural'. One trend that has already emerged is the use of the descriptor 'all natural' on the labelling of those drinks which have now divested themselves of artificial sweeteners, preservatives, colourants and flavourings.

Is HFCS a natural sweetener? After all, it is derived from corn. Not according to the US Center for Science in the Public Interest. CSPI states that it may sound like it comes from corn in the same way sugar comes from sugar cane or sugar beets, but HFCS is created by a complex industrial process. The fact that chemical bonds are broken and rearranged in the production negates any claim to 'all natural' status, says CSPI.

Using the threat of legal action, CSPI has successfully persuaded both Cadbury Schweppes and Kraft Foods to remove the words 'all natural' from packs of their respective drinks 7UP and Capri Sun, both of which use HFCS as the sweetening agent.

However, the Corn Refiners Association of Washington DC makes the point that HFCS, like sugar and honey, is natural. President Audrae Erickson says it contains no artificial or synthetic ingredients or colour additives, and meets the US Food and Drug Administration's policy for use of the term 'natural'.

Erickson points out that there is no consensus among scientists that HFCS is a unique contributor to obesity. Dr Walter Willett, chairman of the Harvard School of Public Health Nutrition Department, has told The New York Times: "There's no substantial evidence to support the idea that high-fructose corn syrup is somehow responsible for obesity."

Furthermore, many parts of the world, including Australia, Mexico and Europe, have rising rates of obesity and diabetes despite having little or no HFCS in their foods and beverages.

So this is a carbohydrate conundrum. What is needed is a sense of perspective.

Writing in The Washington Times on 6 December 2006, Dr Arthur Frank, medical director of the George Washington Weight Management Programme, acknowledges the rise in obesity in countries where HFCS is not used, suggesting that HFCS itself is not the problem, but he adds: "That doesn't mean that you can consume unlimited amounts of sugar or HFCS. Both contain the same number of calories, but there's nothing ominous about either. Just like all of life and eating, moderation is obligatory."

The US is not going to solve its obesity problem simply by attacking one form of refined carbohydrate. Consumers should be fully informed as to the calorie content of what they are drinking, so that they can take responsibility for the control of their own weight.

That's easy then. All we have to do is find a consensus between academics, public health advocates, retailers and food beverage producers on nutritional labelling… Oh dear.