The increasing use of high-fructose corn syrup as an artificial sweetener has been linked to the obesity epidemic and kidney disease. In the industrial preparation process, in which some glucose molecules are converted into fructose, a specific ratio of sugars is created. The complex molecular chemistry of high-fructose corn syrup has several important implications in your dietary health.
High-Fructose Corn Syrup
High-fructose corn syrup, or HFCS, is commonly used as a sweetener in place of sucrose, or common table sugar. The manufacturing process converts the glucose in corn syrup into fructose, which produces a glucose/fructose mixture of varying proportions. For example, HFCS 55 contains 55 percent fructose and 42 percent glucose and is comparable in sweetness to sucrose; the number in the HFCS name indicates the percentage of fructose.
DIsaccharide
High-fructose corn syrup is composed of a mixture of two simple sugar molecules, both of which are classified as "monsaccharides." The complexity of HFCS lies in the conversion process that occurs during manufacturing. Using the enzyme glucose isomerase, glucose molecules in corn syrup are converted to fructose molecules, according to the article "High Fructose Corn Syrup: Production, Uses and Public Health Concerns." This creates an interesting situation, because naturally occurring sugar, known as sucrose, is a more complex sugar molecule composed of fructose and glucose subunits. Known as a disaccharide molecule, sucrose is digested into fructose and glucose molecules. Therefore, in the manufacture of HFCS, the enzyme glucose isomerase is producing the same breakdown products your digestive system produces when you consume sucrose.
The Process of Digestion
In essence, eating HFCS is like eating sucrose that has already been digested by a machine. By completing this initial step in the process of digestion, your body is able to better access the sugar in your diet. This feature enables you to absorb more calories with each meal; HFCS has a high "glycemic index," because it is readily absorbed and rapidly increases blood sugar when consumed. For a contrasting example on the other end of the glycemic index spectrum, consider fiber; this food source is composed of large, complex, branching carbohydrate polysaccharide molecules. Your body has difficulty breaking these complex structures down, thus preventing the rapid increase in blood sugar seen in carbohydrates with high glycemic indexes.
Consequences of Complex Sugar Structure
An article from the journal "Trends in Endocrinology and Metabolism" describes the effect of fructose on the process of lipogenesis, or fat production and storage. The paper describes the complex metabolic pathways that are activated by dietary HFCS, ultimately leading to lipogenesis in the liver and nonalcoholic fatty liver disease. A separate article on "The Effect of Fructose on Renal Biology and Disease" describes the effect of excessive fructose ingestion on kidney health; specific syndromes linked to dietary fructose include glomerular hypertension, renal inflammation, and tubulointerstitial injury.
References
- "Current Hypertension Research"; The Role of High-Fructose Corn Syrup in Metabolic Syndrome and Hypertension; L. Ferder, et al.; April 2010
- "Trends in Endocrinology and Metabolism"; Fructose Induced Lipogenesis: From Sugar to Fat to Insulin Resistance; V.T. Samuel; February 2011
- "American Journal of Clinical Nutrition"; Straight Talk About High-Fructose Corn Syrup; JS White, et al.; December 2008
- "Journal of the American Society of Nephrology"; The Effect of Fructose on Renal Biology and Disease; RJ Johnson, et al.; December 2010
- "Biotechnology and Molecular Biology Review"; High Fructose Corne Syrup: Production, Uses and Public Health Concern. Kay Parker, et al.; September 2010
- "Microbiological Reviews"; Molecular and Industrial Aspects of Glucose Isomerase; Snehalata H. Bhosale, et al.; June 1996
Member Comments