Single food ingredient the cause of obesity ? New study has industry up in arms

Investigating food consumption patterns over the past 35 years, scientists found that in the 20 years from 1970 to 1990 the consumption of the popular soft drink sweetener, high fructose corn syrup, leapt by a massive 1000 per cent.

"HFCS now represents more that 40 per cent of caloric sweeteners added to foods and beverages and is the sole caloric sweetener in soft drinks in the US,"​ said George Bray and colleagues in a recent issue of the American Journal of Clinical Nutrition​.

The researchers suggest that this rapid trajectory of HFCS consumption, and processed carbohydrates in general, through food and drinks could be to blame for the steep rise in obesity.

A second study released this week in the American Journal of Clinical Nutrition​ by researchers at the Harvard School of Public Health claims a link between consumption of refined carbohydrates and type 2 diabetes.

Looking at 100 years of data from the US Department of Agriculture and Centre for Disease Control and Prevention, the researchers suggest that people have eaten the same amount of carbohydrates a day on average - 500 grams - since 1909. But instead of whole grains and vegetables, people are receiving more and more of the carbohydrates in the form of processed grains and sugars, with the majority coming from corn syrup.

The scientists, led by Dr. Lee Gross, at the Inter-Medic Medical Group in North Port, Florida, drew a link to the rising number of cases of type-2 diabetes, caused by the body's increasing inability to properly metabolise sugars.

But the industry hotly refuted the claims. "It is incorrect and even misleading to suggest the consumption of a specific food or food ingredient is the cause of obesity and the rising rate of type 2 diabetes in this country,"​ said Robert Earl, a director of nutrition policy for the $500 billion industry body, the National Food Processors Association.

He added that excess calories 'from any source' could lead to weight gain 'in the absence of physical activity,'.

"Diabetes rates are rising in many countries around the world that use little or no high fructose corn syrup in foods and beverages. This supports findings by the Centre for Disease Control and the American Diabetes Association which states the primary causes of diabetes are obesity, advancing age and heredity,"​ commented Audrae Erickson, president of the Corn Refiners Association​ in a statement.

She added that the North Port study had 'numerous and significant factual errors and misrepresentations that mislead the American public,'.

High fructose syrups, known as isoglucose in Europe, kicked off in the US in the 1970s when the country developed new technologies to process this bulk calorific sweetener. The ingredient, an alternative to sucrose, rapidly gained in popularity and is now used by the soft drinks giants Coca-Cola and Pepsi-Co.

High fructose corn sweeteners begin with enzymes which isomerise dextrose to produce a 42 per cent fructose syrup. By passing 42-HFCS through a column which retains fructose, refiners draw off 90 per cent HFCS and blend it with 42-HFCS to make a third syrup, 55-HFCS. Further processing produces crystalline fructose.

According to the US corn refining industry, in 2003 corn sweeteners, sourced from US corn farmers and the leading global corn suppliers, supplied more than 56 per cent of the US nutritive sweetener market.

Isoglucose use in the EU falls far behind the US, princially due protectionist policies that seek to secure the EU's sugar regime and control sucrose alternatives, such as isoglucose. This means that isoglucose, used as well as soft drinks in canned fruits, condiments, ice cream and frozen desserts, is entitled to only a small niche market.

F.O.Licht tells FoodNavigator.com​ that the leading isoglucose suppliers in Europe are Amylum, the number one isoglucose player and also a subsidiary of UK sugar giant Tate & Lyle, and US agri-titan Cargill.

The recent acquisition of French starch and derivatives firm Cerestar bolstered Cargill's position in the largely monopolised European isoglucose market.

Production of isoglucose in the EU 25 topped 540,000 tonnes last year, a figure similar to consumption because the ingredient can not be easily stored, and resulting in little stock changes from one year to the next.

EU accession country Hungary tops the bill as the leading producer in the bloc, turning out 137,000 tonnes of isoglucose. Spain falls into the number two position with 82,000 tonnes, followed by Belgium with 70,000 and Slovakia producing 55,000 tonnes.

Tate & Lyle and Agrana have a joint isoglucose venture in Hungary called Hungrana.