Health fears over use of sweetener
Coca Cola and Pepsi switched to sweetening their US products with HFCS in 1984
30 Oct 2009
A sugary ingredient that is commonly used to flavour processed foods and soft drinks could be a major cause of high blood pressure, new research has found.
High fructose corn syrup (HFCS) is abundant in many types of foods and beverages, including fizzy drinks, biscuits, ketchup and bread, and was originally viewed as a “healthy” method of sweetening.
Its introduction 20 years ago has caused consumption of the fruit sugar fructose to rise sharply, alongside increasing levels of obesity.
Although healthy amounts of fructose exist naturally in fruit, excessive amounts of the sugar may be harmful. Studies have already shown that large quantities of fructose cause the liver to pump fats into the bloodstream that may damage arteries.
Links to insulin resistance and diabetes have been documented, with research also concluding that when people consume artificial sweeteners they have an increased desire to keep eating.
Researchers who carried out the new study in the US looked at more than 4500 adults with no prior history of high blood pressure.
Fructose intake was calculated by asking participants to rate their consumption of foods such as fruit juices, soft drinks, bakery products and confectionery.
The study found that people who ate or drank more than 74 grams of fructose per day, the equivalent to 2.5 sugary soft drinks, increased their risk of developing high blood pressure.
“Normal” blood pressure is said to be a reading of around 120/80 millimetres of mercury (mmHg) depending on age. The first figure relates to blood pressure when the heart is actively beating, the second is the reading of the blood pressure between beats.
More than 74 grams of fructose a day increased the chances of a higher reading of 135/85mmHg by 28%, the study found. It also increased the likelihood of a higher reading of 140/90mmHg by 36% and 160/100mmHg by 87%.
Since it was first developed in the United States in the 1970s, HFCS has widely replaced sugar as a result of the vast corn subsidies offered to farmers and the high price of sugar tariffs and quotas.
While there is no naturally occurring fructose in corn syrup, an enzyme was discovered in the 1950s that could turn its glucose content into fructose. This process was refined in the 1970s, leading to the mass production of HFCS. The product is also easier to blend and transport given its liquid form.
HFCS is now preferred over cane sugar among the vast majority of American food and drink manufacturers thanks to its low production costs. Coca Cola and Pepsi switched to sweetening their products with the substance in 1984, but continue to use sugar in other nations. Four main companies in the US control 85% of the HFCS market.
The use of HFCS in Europe has not been as widespread as in America. In 2005, the EU set a production quota of 303,000 tonnes a year. By contrast, the EU produced an average of 18.6 million tons of sugar annually between 1999 and 2001.
Americans today consume 30% more fructose than they did 20 years ago and up to four times more than they did 100 years ago, those behind the latest study reported yesterday at the annual meeting of the American Society of Nephrology in California.
Dr Diana Jalal, from the University of Colorado, and colleagues wrote in their paper: “These results indicate that high fructose intake in the form of added sugars is significantly and independently associated with higher blood pressure levels in the US adult population with no previous history of hypertension.”
Further work was needed to see if lowering fructose consumption could normalise blood pressure, Dr Jalal said.