The super-sized myth surrounding high fructose corn syrup is that it is uniquely responsible for causing obesity. The only problem with that is that there’s no actual evidence to support this claim.
Research does show, however, that obesity results from an imbalance of calories consumed and calories burned. Research also does not directly connect obesity to one specific food or ingredient.
"After studying current research, the American Medical Association (AMA) today concluded that high fructose syrup does not appear to contribute to obesity more than other caloric sweeteners..." - American Medical Association, June 2008
Mark Haub, Ph.D., answers the question: Does high fructose corn syrup cause obesity?
 Lack of findings for the association between obesity risk and usual sugar-sweetened beverage consumption in adults - A primary analysis of databases of CSFII-1989-1991, CSFII-1994-1998, NHANES III, and combined NHANES 1999-2002.
We’ve seen claims that high fructose corn syrup is unnatural. Yet high fructose corn syrup is made from corn, a natural grain product.
There are no artificial or synthetic ingredients and no color additives in high fructose corn syrup. It is refined with similar production methods to other sugars, making it no more “processed” than any other sweetener.
High fructose corn syrup meets the Food and Drug Administration’s (FDA) requirements for use of the term ‘natural.’
Jim Laidler, M.D., answers the question: Is High Fructose Corn Syrup Unnatural?
 Study: Straight talk about high-fructose corn syrup: what it is and what it ain't, John S White, American Journal of Clinical Nutrition 2008
Similar to misunderstandings around obesity, high fructose corn syrup also has no unique link to causing diabetes. This fact has been supported by the U.S. Centers for Disease Control and the American Diabetes Association who state that the primary causes of diabetes are obesity, advancing age and heredity. In fact, the U.S. Department of Agriculture (USDA) data shows that per capita consumption of high fructose corn syrup has been declining in recent years, while the incidence of obesity and diabetes in the United States continues on the rise.
The ratio of fructose in the diet is not higher now than it was 30 years ago. Fructose is a natural simple sugar found in sugars, vegetables, fruits and honey. Significant confusion has stemmed from recent studies that examined pure fructose in excess amounts and linked it to obesity, a precursor to diabetes. The results were then inappropriately connected to high fructose corn syrup, even though the two substances are vastly different. The studies included abnormally high levels of fructose that are never consumed in a normal human diet. High fructose corn syrup and table sugar both have fructose in them but it is combined with glucose which balances the metabolic effects of fructose.
Jim Laidler, M.D., answers the question: Does high fructose corn syrup have a lot of fructose in it?
Yes, there are no safety concerns. The safety of high fructose corn syrup is based on science and expert review accumulated over the past 40 years. In 1983, the FDA listed high fructose corn syrup as “Generally Recognized as Safe” (known as GRAS status) for use in food and reaffirmed that ruling in 1996. GRAS recognition by the FDA is important because it recognizes a long history of safe use as well as adequate scientific studies proving an ingredient’s safety. GRAS status is maintained indefinitely unless the FDA has a new reason to question an ingredient’s safety, in which case it will then look into maintaining or revoking the GRAS status.
Lara Field, R.D., answers the question: Is HFCS a safe ingredient?
John White, Ph.D. noted, “Its safety was never seriously doubted because expert scientific panels in every decade since the 1960s drew the same conclusion: sucrose, fructose, glucose, and, latterly, HFCS did not pose a significant health risk, with the single exception of promoting dental caries [tooth decay].”
In addition to government-convened expert panels, professional organizations have also confirmed the safety of high fructose corn syrup, including the American Medical Association (AMA) and the Academy of Nutrition and Dietetics (formerly the American Dietetic Association).
Insulin is responsible for the uptake of glucose into cells and the lowering of blood sugar, a vital control process for metabolism. Both sugar and high fructose corn syrup have largely the same effect on insulin production. Among common sweeteners, pure glucose triggers the greatest insulin release, while pure fructose triggers the least. Both table sugar and high fructose corn syrup trigger about the same intermediate insulin release because they contain nearly equal amounts of glucose and fructose.
The body metabolizes the sugars in high fructose corn syrup the same way it does table sugar, honey and many fruits. Since these sweeteners all have approximately equal ratios of fructose and glucose, these simple sugars are absorbed into the blood stream in similar ways.
Jim Laidler, M.D., answers the question: How is high fructose corn syrup metabolized by the body?
Multiple studies have confirmed this similar response on different aspects of metabolism:
- Leptin and Ghrelin - Kathleen J. Melanson, et al., at the University of Rhode Island reviewed the effects of high fructose corn syrup and sugar on circulating levels of glucose, leptin, insulin and ghrelin in a study group of lean women. The study found “no differences in the metabolic effects” of high fructose corn syrup and sugar.
- Triglycerides - A study by Linda M. Zukley, et al., reviewed the effects of high fructose corn syrup and sugar on triglycerides in a study group of lean women. This short-term study found “no differences in the metabolic effects in lean women [of high fructose corn syrup] compared to sucrose.”
- Uric Acid - Joshua Lowndes, et al., reviewed the effects of high fructose corn syrup and sugar on circulating levels of uric acid in a study group of lean women. This short-term study found “no differences in the metabolic effects in lean women [of high fructose corn syrup] compared to sucrose.”
There is no credible research demonstrating that high fructose corn syrup affects your feelings of fullness any differently than sugar or other sweeteners.
James Krieger, M.S., answers the question: Does high fructose corn syrup affect my feelings of fullness?
As researchers have pointed out:
Pablo Monsivais, et al., at the University of Washington: Found that beverages sweetened with sugar and high fructose corn syrup, as well as 1% milk, all have similar effects on feelings of fullness.
Stijn Soenen and Margriet S. Westerterp-Plantenga, at Maastricht University in The Netherlands: Found “no differences in satiety, compensation or overconsumption” between milk and beverages sweetened with sugar and high fructose corn syrup.
Tina Akhavan and G. Harvey Anderson at the University of Toronto: Found that sugar, high fructose corn syrup, and 1:1 glucose/fructose solutions do not differ significantly in their short-term effects on subjective and physiologic measures of satiety and food intake at a subsequent meal.
The Glycemic Index (GI) is a ranking of foods, beverages and ingredients based on their immediate effect on blood glucose levels. The GI measures how much blood sugar increases over a period of two or three hours after a meal. Sugar and honey, both have moderate GI values that range from 55 to 60 and an index of up to 100. Although it has not yet been specifically measured, high fructose corn syrup is expected to have a moderate GI due to its similar composition to honey and sugar.
However, it is important to keep in mind that the body does not respond to the GI of individual ingredients, but rather to the GI of the entire meal. Since added sugars like sugar and high fructose corn syrup typically contribute less than 20 percent of calories, they are a minor contributor to the overall GI in a normal diet.
 61 Fed. Reg. 43447 (August 23, 1996), 21 C.F.R. 184.1866. Direct food substances affirmed as Generally Recognized as Safe; High Fructose Corn Syrup - Final Rule.
 U.S. Department of Agriculture, Economic Research Service. 2009. Calories: average daily per capita calories from the U.S. food supply, adjusted for spoilage and other waste. Loss-Adjusted Food Availability Data.
Food allergies are caused by your body’s response to certain proteins in foods. Nearly all of the corn protein is removed during the production of high fructose corn syrup. Moreover, the trace protein that remains likely bears little immunological resemblance to allergens in the original kernel.
A number of cereal grains, including wheat, rye, barley and corn, can cause allergic reactions in some individuals. Although the amount of corn protein found in high fructose corn syrup is extremely low, a person who is allergic or sensitive to corn and corn products should seek and follow the advice of medical professionals about consuming products with HFCS. 
Jim Laidler, M.D., answers the question: Can you be allergic to high fructose corn syrup?
High fructose corn syrup is made from corn using a process called wet milling. In general, the process includes:
1. Steeping corn to soften the hard kernels
2. Physically separating the kernel into its separate components (starch, corn hull, protein and oil)
3. Breakdown of starch into glucose
4. Use of enzymes to invert glucose to fructose
5. Removal of impurities
6. Blending of glucose and fructose to make HFCS-42 and HFCS-55
 White JS. 1992. Fructose syrup: production, properties and applications, in FW Schenck & RE Hebeda, eds, Starch Hydrolysis Products – Worldwide Technology, Production, and Applications. VCH Publishers, Inc. pp. 177-200.
According to Keith-Thomas Ayoob, Ed.D., RD, FADA, a practicing pediatric nutritionist with 25 years of experience, people often assume that sugar causes hyperactivity because of all the nutritional myths and misinformation they’ve read or heard about. ADHD is a definable medical condition, but it’s not caused by sugar, high fructose corn syrup or any other form of sweetener. This is the conclusion of dozens of well-controlled studies. High fructose corn syrup and other sugars may give you a quick burst of energy, but it is short-lived and relatively mild.
Jim Laidler, M.D., answers the question: Does High Fructose Corn Syrup cause ADHD?
No mercury or mercury-based technology is used in the production of high fructose corn syrup in North America. High fructose corn syrup is safe and does not contain quantifiable levels of mercury.
A study was published claiming the opposite but independent experts have performed their own evaluations and confirmed that HFCS is mercury-free. One of the nation’s leading experts in mercury contamination, Dr. Woodhall Stopford, MD, MSPH, of Duke University Medical Center confirmed this assessment. You can view his analysis and conclusion by visiting http://duketox.mc.duke.edu/recenttoxissues.htm and clicking on the link under the Mercury heading.
Jim Laidler, M.D., answers the question: Is there mercury in high fructose corn syrup?
Reports Regarding High Fructose Corn Syrup (HFCS) and Mercury Misleading: ChemRisk discussing report flaws