High Fructose Corn Syrup High Fructose Corn Syrup (HFCS) High Fructose Corn Syrup (HFCS) HFCS - History HFCS - History HFCS - History HFCS History

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1 High Fructose Corn Syrup Dianne Koehler, MNT High Fructose Corn Syrup (HFCS) u What is HFCS u HFCS history u Carbohydrate biochemistry u HFCS biochemistry u Health implications High Fructose Corn Syrup (HFCS) u Sweetener made from corn the most widely grown crop in the U.S. (largest GMO crop) u Corn is milled, separated into starch and fiber u Starch is cooked down to a slurry (from which corn syrup is derived) u Enzymes are added to convert most of the large sugar molecules into single sugars - glucose and fructose u Then filtered into final liquid product HFCS - History u The process first introduced in 1957 (USA) u Industrial production techniques developed late 1960s/early 1970s (Japan) u 1975 (USA) rapidly introduced into processed foods quickly became the dominant sweetener in processed foods u Baked goods, soda, confections, etc. u Designed to have taste/sweetness ~equivalent to sugar to be used as a sugar replacement 5 HFCS - History u Less expensive than sugar (sucrose) u Uses commodity corn #1 government subsidized crop u Sugar beets also have government subsidies - #20 u Easier to store and transport 1

2 u Easier to store and transport u Enhances sweetness of other sweet flavors u Extends shelf life of processed foods more stable, inhibits microbial growth u More desirable mouth feel and texture retains moisture and does not crystalize 6 HFCS - History u US Department of Agriculture food consumption tables from 1967 to The consumption of HFCS increased 1000% between 1970 and 1990 u By 2004 HFCS represents 40% of caloric sweeteners added to foods and beverages and is the sole caloric sweetener in soft drinks in the United States u Estimated average intake for Americans over the age of two = 132 kcal per day u The top 20% of consumers of caloric sweeteners ingest 316 kcal from HFCS per day HFCS History u HFCS is a misnomer it is not high in fructose u Named HFCS because it has a higher fructose content than corn syrup, which has no fructose (pure glucose) u Two HFCS formulations: u 42% fructose used in baked goods, packaged foods, candies u 55% fructose used in soft drinks u Corn Refiners Association petitioned FDA to change the name to Corn Sugar not approved Carbohydrate Biochemistry u Three monosaccharides smallest carbohydrate units u Fructose, Glucose, Galactose u Fructose (sweetest) naturally occurs in fruits, honey, agave, some vegetables Carbohydrate Biochemistry 2

3 u Three disaccharides two monosaccharides chemically bonded together u Sucrose, Lactose, Maltose 10 Carbohydrate Biochemistry u Sucrose table sugar, unrefined sugars (Rapadura, Succanet, Turbinado) u Disaccharide derived from sugar cane or sugar beets; sugar maple sap, date palm, sorghum u 50% glucose, 50% fructose HFCS Biochemistry u HFCS u The glucose and fructose are not bound together they are free sugars u Fructose content is manipulated to be either 42% or 55% depending on desired end use u 42% has less fructose than sugar (less sweet) u 55% fructose content relatively equivalent to sugar HFCS Biochemistry u HFCS vs. Sucrose u Sucrose disaccharide; fructose and glucose are equal concentrations u Must be digested within intestine u HFCS monosaccharides (free sugars) Fructose Health Implications u Fructose does not stimulate insulin because insulin only responds to glucose (and some amino acids) u Initially touted as a diabetic safe sweetener u Fructose does not stimulate leptin production a key hormonal modulator of the hunger signal u Fructose is rapidly taken up by the liver u Some converted to glucose when released into blood will stimulate insulin 3

4 u Some converted to glucose when released into blood will stimulate insulin u Remaining converted to fats 14 Fructose Health Implications u Human studies of fructose negative metabolic consequences: u Increases triglycerides (fats) u Limits fatty acid breakdown by the liver contributes to fatty liver u Increases cholesterol (as part of lipid transport) u Increased oxidation of LDL cholesterol u Increases insulin levels over time results in insulin resistance u Stimulates adiposity u Increases production of uric acid (cause of gout) 15 Fructose Health Implications u Fructose vs. Glucose u In the liver, fructose bypasses a regulatory mechanism in its metabolism that glucose must endure u Causes fructose to be more readily converted to triglycerides (fat) by the liver u In moderation, all dietary glucose can primarily be used for energy u In excess, glucose causes same metabolic consequences as fructose; with fructose it happens faster 4

5 16 u Why is HFCS vs. sucrose more associated with the negative health consequences of fructose: u The marked increase in HFCS consumption has resulted in excessive increase in fructose consumption primarily in soda u The fructose is free readily absorbed from intestine (bypasses the digestion step that sucrose undergoes) u Fructose absorbed and metabolized differently than glucose independent of regulatory mechanisms 17 u Uric Acid u Causative factor in endothelial dysfunction u Impaired ability to properly constrict and dilate arteries u Associated with high blood pressure and atherosclerosis u Induces C-reactive protein production u A marker of increased inflammation u Causes gout 5

6 18 u All carbohydrate derived sweeteners contain sucrose, or some component of the monosaccharides glucose and fructose u Corn syrup is only glucose u Maple syrup is primarily sucrose u Dark B grade has more free monosaccharides u HFCS is either 42% or 55% fructose u Honey is 40%-50% fructose u Agave is 48%-75% fructose u An excess of any carbohydrate sweetener will contribute to metabolic dysfunctions 19 u Strategies to protect against negative consequences of fructose or glucose overconsumption u Limit sweeteners in any form refined sugar, unrefined sugar, syrups, etc. u Eliminate liquid based HFCS consumption soda and HFCS sweetened juices u Minimize free fructose found in HFCS, and even agave, honey 6

7 20 References u EWG Farm Subsidy Database u Consuming fructose-sweetened, not glucose sweetened, beverages increases visceral adiposity and lipids and decreases insulin sensitivity in overweight/obese humans. The Journal of Clinical Investigation Volume 119 Number 5 May 2009 u Consumption of high-fructose corn syrup in beverages may play a role in the epidemic of obesity. Am J Clin Nutr 2004;79: American Society for Clinical Nutrition u Intermediary metabolism of fructose. Am J Clin Nutr 1993;58 (suppl):754s-65s American Society for Clinical Nutrition u Hypothesis: Could Excessive Fructose Intake and Uric Acid Cause Type 2 Diabetes? Endocrine Reviews 30(1): by The Endocrine Society u Potential role of sugar (fructose) in the epidemic of hypertension, obesity and the metabolic syndrome, diabetes, kidney disease, and cardiovascular disease1. Am J Clin Nutr 2007;86: American Society for Nutrition 7