Fructose and Type 2 Diabetes
High-fructose corn syrup comprises any of a group of corn syrups that has undergone enzymatic processing to convert some of its glucose into fructose to produce a desired sweetness. Pure, dry fructose is a very sweet, white, odorless, crystalline solid and is the most water-soluble of all the sugars. The primary reason that fructose is used commercially in foods and beverages, besides its low cost, is its high relative sweetness (almost twice the sweetness of sucrose). A new study indicates that large amounts of high fructose corn syrup (HFCS), a sweetener found in national food supplies across the world, may be a contributory factor to the rising global epidemic of type 2 diabetes.
Natural sources of fructose include fruits, vegetables (including sugar cane), and honey.
Fructose is also found in the synthetically manufactured sweetener, high-fructose corn syrup. Hydrolyzed corn starch is used as the raw material for production of HFCS. Through the enzymatic treatment, glucose molecules are converted into fructose. There are three types of HFCS, each with a different proportion of fructose: HFCS-42, HFCS-55, and HFCS-90. HFCS-55 is used as sweetener in soft drinks, whereas HFCS-42 is used in many processed foods and baked goods.
The study by researchers from the University of Oxford and the University of Southern California reports that countries that use HFCS in their food supply had a 20 per cent higher prevalence of diabetes than countries that did not use HFCS. The analysis also revealed that HFCS's association with the significantly increased prevalence of diabetes occurred independently of total sugar availability and obesity levels.
The paper reports that out of 42 countries studied, the United States has the highest consumption of HFCS per head of population at a rate of 25 kilograms or 55 pounds per year. The second highest is Hungary, with an annual rate of 16 kilograms or 46 pounds per head of population. Canada, Slovakia, Bulgaria, Belgium, Argentina, Korea, Japan and Mexico are also relatively high HFCS consumers. The United Kingdom was among the countries with much lower levels of consumption — at less than 0.5 kilogram per head of population.
Countries with a higher use of HFCS had an average prevalence of type 2 diabetes of eight per cent compared to 6.7 percent in countries not using HFCS, says the study.
"This research suggests that high fructose corn syrup can increase the risk of type 2 diabetes, which is one of the most common causes of death in the world today," said Professor Stanley Ulijaszek, Director of the Institute of Social and Cultural Anthropology at the University of Oxford, who co-authored the study.
The article published in the journal Global Public Health proposes that the link is probably driven by higher amounts of fructose in foods and drinks that contain HFCS. Fructose and glucose are both found in ordinary sugar (sucrose) in equal amounts, but HFCS has a greater proportion of fructose. The higher fructose content makes HFCS sweeter and provides processed foods with greater stability and a better appearance because it produces a more consistent browning when foods made with higher fructose are baked.
Professor Ulijaszek said: "Many people regard fructose as a healthy natural sugar from fruit, and that's true. Natural fructose found in fruit for example, is fine: the 10 grams or so of fructose in an apple is probably released slowly because of the fiber within the apple and because the fructose is inside the cells of the apple. But a number of studies have shown that high intakes of non-fruit based fructose is especially difficult for the body to metabolize, and is a risk for type 2 diabetes because fructose and sucrose are not metabolically equivalent. Our study shows an ecological relationship that suggests there are potential risks in consuming high levels of high-fructose corn syrup."
For further information see Fructose.
Crystals image via Wikipedia.