“High-Fructose Corn Syrup will make you fat!” “High-Fructose Corn Syrup is the reason you can’t lose weight.” “High-Fructose Corn Syrup is worse for you than table sugar.” The list goes on and on of the various claims made about high-fructose corn syrup (HFCS) throughout the dieting community and popular media headlines. And while these claims have become almost law to many who are trying to lose weight, is there actually any truth behind them? Is high-fructose corn syrup itself really to blame for the current obesity epidemic sweeping America?
Now, before I get too far into this, I would like to clarify the specific question we are addressing in today’s article: Is high-fructose corn syrup itself worse for you (I am defining “worse for you” in this context, as having greater negative outcomes in terms of fat-loss and body-composition), compared to traditional table sugar (also called sucrose) in a normal, free-living environment? Therefore, if everything is controlled for (Total caloric intake, carbohydrate intake, etc.), if one consumes “x” amount of HFCS, is this going to result in a different outcome than if they consume “x” amount of table sugar in regards to weight-loss and body-composition? Comparing the differences between pure glucose, and pure fructose metabolism is beyond the scope of this article. Now, let’s dive in…
HIGH-FRUCTOSE CORN SYRUP VS. TABLE SUGAR. WHAT’S THE DIFFERENCE?
I figured the best place to start would be defining these two terms. What exactly is the difference between these two carbohydrates?
TABLE SUGAR (SUCROSE)
Traditional table sugar, also known as sucrose, is a disaccharide (meaning a molecule composed of two monosaccharides), composed of an equal 1:1 ratio of glucose to fructose. This means that traditional table sugar is 50% glucose, and 50% fructose.
HIGH-FRUCTOSE CORN SYRUP
HFCS is a disaccharide just like traditional table sugar, and is also composed of the same two monosaccharides: glucose and fructose. Where the difference lies between the two (HFCS and table sugar) is the ratio of glucose to fructose molecules. As stated above, in traditional table sugar this ratio is 1:1 (50% glucose and 50% fructose). In HFCS, this ratio can very slightly depending on the form used. There are 3 main types of HFCS: HFCS-42, HFCS-55 and rarely used HFCS-90. The respective number of each represents the amount of fructose contained in that variety, for example: HFCS-42 is composed of 42% fructose, and 58% glucose.
So as we can see, the difference between the structures of these two sweeteners (HFCS and table sugar), is very small, and lies in the difference between the amount of fructose present in each. The primarily used forms of HFCS are the ones which contain 42% and 55% fructose, with HFCS-90 being used only in rare circumstances. When compared to traditional table sugar (50% fructose), we can see that the actual difference between the two is pretty insignificant. Now the question becomes, in a free living environment, where people consume a mixed diet composed of a wide variety of foods, is this difference in the amount of fructose really enough to make a difference?
LET’S TAKE A LOOK AT A STUDY…(I WILL CITE THIS STUDY AT THE END AT THE END FOR THOSE WHO WOULD LIKE TO VIEW IT IN ITS ENTIRETY)
The study was a randomized, double-blind trial, meaning the participants were randomly placed in groups, and neither the participants nor the researchers knew which group was receiving which intervention. The subjects were 162 male and female overweight/obese individuals between the ages of 25 and 60 years old.
There were 4 different intervention groups, who each received either 10% or 20% of their total daily calories from added table sugar (sucrose) or HFCS. These sugars were consumed as a component of a mixed-nutrient, hypocaloric meal plan in a free living environment (Meaning these subjects weren’t held captive in the lab for 12 weeks). The subjects also completed a fitness walking program in conjunction with their dietary intervention.
The study lasted for 12 weeks, and examined measurements of body-weight, waist circumference and body-composition (Via DXA scan) both prior to, and after completing the study.
As mentioned above, these diets were hypocaloric, meaning the participants were prescribed diets that were lower in calories than the amount needed to maintain their current body-weight.
At the end of the study, the researchers found that all 4 groups (those receiving 10% HFCS, 20% HFCS, 10% Sucrose & 20% Sucrose), lost similar amounts of weight, and had similar reductions in waist-circumference and body-fat levels.
The researchers concluded, that at the typical population consumption level of added sugars, there does not appear to be a difference between HFCS and table sugar in terms of weight-loss and associated improvements in body-composition.
Here are a few excerpts from the discussion:
“Initial concern was raised that there might be a unique relationship between obesity and the consumption of HFCS because of the temporal association between increased use of HFCS in the American food supply to the increased prevalence of obesity between 1970 and 2000 . Despite the popularity of this suggestion, there are numerous reasons this hypothesis should be discarded. Firstly, the temporal association between HFCS and obesity ended in 1999, when HFCS use began to diminish . Secondly, numerous countries around the world have a similarly increasing prevalence of overweight and obesity as the United States, but do not use HFCS. Lastly, subsequent research studies have shown there is no difference between HFCS or sucrose in any metabolic parameter measured in human beings including glucose, insulin, leptin, ghrelin, triglycerides, uric acid, appetite or calories consumed at the next meal [31, 32, 37]. Both the American Medical Association  and the American Dietetic Association  have issued statements declaring that there is nothing unique about HFCS that leads to obesity. Both of these statements note that all caloric sweeteners contain calories and should be used in moderation. The present data further support the theory that, when consumed at levels up to the 50th percentile for fructose in the context of a hypocaloric diet, neither HFCS nor sucrose impedes weight loss. These data provide further support to the concept that overall caloric consumption rather than one particular component of the diet is most important for achieving weight loss.”
“Our data demonstrate that equally hypocaloric diets provoked similar weight changes regardless of type or amount of sugar consumed.”
Now although everything looks fine and dandy at this point, I want to make you aware of some of the limitations to this study:
• It was conducted in a free-living environment, which means all of the data (Food consumption, physical activity, etc.) was self-reported. Because experiments like this are extremely difficult to conduct in the context of a confined lab for 12 weeks, we have to rely largely on the participants being honest and accurate with the information they report to the researchers.
• The compliance with consuming the prescribed sweetener was very high (~96.6%), however again, this was also self-reported data.
• Due to the design of the participant’s meal plan, the researchers couldn’t measure the actual amount of HFCS or sucrose consumed through whole foods in the diet. Only what was prescribed additionally as the added sweetener could be calculated. However, the dietary plans utilized lists of foods similar in fructose content so that participants in all four intervention groups were prescribed a comparable amount of fructose from these other sources.
• This study was funded by the Corn Refiners Association.
TO WRAP EVERYTHING UP…
Although this study had its limitations, when taking its results in consideration with the other literature on this topic, as well as with the similar molecular structure between HFCS and sucrose, the results look promising. The purpose of this article was not to persuade you to go out and to start consuming copious amounts of high-fructose corn syrup. It was merely to bring up the current data we have about what HFCS really is, and whether or not it is the evil, “diet killer” so many claim. Ultimately though, it is up to you to decide whether or not you’d like to avoid consuming this widely used added sugar. It certainly won’t hurt you to do so, however in the context of a properly controlled diet, total caloric consumption, and carbohydrate intake, it is unlikely that doing so will provide any additional fat-loss benefits. It is when these things are NOT accounted for, that cause the entire dynamic of this issue to change.
Lowndes, J., Kawiecki, D., Pardo, S., Nguyen, V., Melanson, K. J., Yu, Z., & Rippe, J. M. (2012). The effects of four hypocaloric diets containing different levels of sucrose or high fructose corn syrup on weight loss and related parameters. Nutrition Journal Nutr J, 11(1). doi:10.1186/1475-2891-11-55
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