By Eddie Childs
Cutting through the controversy surrounding high-fructose corn syrup
Back in the late 1970s, high-fructose corn syrup (HFCS) became a mainstay for the food industry as a cheap sweetener for processed products. Not insignificantly, this occurred right around the same time that waistlines worldwide began to grow. And while the supersizing of Earth’s population is likely attributable to numerous different factors, the ubiquity of HFCS in the developed world’s food supply has become undeniable.
“It’s nearly impossible to avoid HFCS if you eat processed foods, since the two often go hand-in-hand,” says Delma De La Fuente, a certified educator at The Living Foods Institute and a student at Life University. “One would have to be vigilant to completely eliminate it—however, awareness is the key to keeping [foods containing HFCS] at bay, as is having the determination to read labels and include more whole and unrefined foods in your diet [as opposed to] refined ones.”
As a food additive, HFCS is found in a seemingly endless variety of foods and beverages including fruit juice, soda, cereal, bread, yogurt, ketchup and mayonnaise. Although a direct correlation has yet to be discovered, HFCS has been implicated in the increase of obesity, cardiovascular disease, diabetes and non-alcoholic fatty liver disease, in addition to reputedly containing traces of mercury.
On the other hand, other research tends to maintain that HFCS isn’t significantly more detrimental to health than common sugar. This is because, as a chemical compound, fructose isn’t drastically different than table sugar. So why does this disconnect exist? Could it be possible that HFCS is, in fact, being demonized?
“The truth is, the evidence is not that conclusive [about the correlation between HFCS and health conditions like obesity and diabetes],” says LIFE Associate Professor of Nutrition Beverley Demetrius, Ph.D. “What we do know is that HFCS is now the sugar of choice for many soft drink beverages and a lot of different products, and we now know that beverage consumption has gone up astronomically for all age groups, and because of that, caloric intake has increased, which is really what causes [people to be] overweight. So, it cannot be said it’s exactly a one-to-one ratio [of HCFS to obesity]. It’s more the caloric intake that has increased.”
HFCS and Human Physiology
The rub of such an argument, of course, lies in the fact that, in and of itself, HFCS may not be particularly harmful to the human body. However, scientific consensus also seems to agree that over-consumption of this compound and regular sucrose are both detrimental to human health. Part of the reason why HFCS (instead of sucrose) has had such a dramatic impact, though, likely lies in the differing biomechanics of glucose and fructose processing and how those processes subsequently affect human consumption habits.
In other words, many theories hold that HCFS lends itself to over-consumption by its very nature. “HFCS basically has been concentrated with fructose,” says Deidre Meiggs, Ph.D, an assistant professor of chemistry at LIFE. “[In its common form, HFCS-55] it’s 55 percent fructose and only 45 percent glucose, so it’s not that much different from sucrose [a 50-to-50-percent, glucose-fructose disaccharide]. The real problem is that glucose creates an insulin response and fructose doesn’t, and people can keep drinking or eating and not have the ‘turn-off’ response [that insulin provides]. So, this is one reason why [HCFS] is, in fact, problematic. Because you don’t have the biochemical response, people tend to consume more, even though your body doesn’t need it.”
Confusingly enough, because fructose doesn’t cause blood-glucose spikes or trigger insulin response, fructose-containing foods have been classified as being “low glycemic” when rated on the glycemic index. Some recent hormonal studies comparing glucose and fructose metabolism, however, have shown these sugars cause drastically different reactions that could link obesity with highly concentrated fructose intake.
According to Demetrius, although fructose itself is a natural sugar, concentrated HFCS is not. “It’s a product that’s broken down into shorter-chain glucose and fructose molecules,” she explains. “The issue is that the amount of fructose that it’s actually broken down into is a little too much for the body to handle as a source of carbohydrates and, in particular, insulin, which has a hard time [managing large amounts of] fructose at one time.”
Fructose Metabolism Patterns
Overall, fructose follows a completely different metabolic pathway from glucose, and it avoids crucial rate-limiting processes in the liver. “Glucose is used by practically every cell in your body, so whenever you ingest glucose, it doesn’t immediately go to your liver; it’s used by your other cells and then [some] of it may end up in your liver,” says Meiggs. “However, fructose basically goes to your liver immediately. Nothing else uses it, but your liver processes it, and then a number of other biochemical processes follow.”
Fructose ingestion also triggers a different hormonal response than glucose. While both Meiggs and Demetrius agree that insulin either isn’t released or is released in lower amounts, numerous studies have also shown that fructose intake can also lower leptin (which regulates energy intake and expenditure, and decreases appetite) and doesn’t reduce the hunger-stimulating peptide and hormone ghrelin. And since these three hormones—leptin, ghrelin and insulin—all play crucial regulatory roles within the body’s food intake processes, myriad repercussions can occur when the body ingests fructose as opposed to glucose.
Concentrated fructose intake also has been linked with other detrimental metabolic conditions aside from obesity. In animal studies conducted by researchers at Princeton, possible links between concentrated fructose intake and insulin resistance have been observed, and it’s been theorized that HFCS could cause decreases in adiponectin, which could, in turn, lead to type 2 diabetes. However, human results in this capacity have been much more variable, leading to some degree of uncertainty regarding a direct correlation.
“In terms of the link with diabetes and obesity—the advent of HFCS is believed to correlate with the obesity epidemic that emerged in the early 1980s, right? Well, that’s because fat became the proverbial enemy,” explains Meiggs. “The fat content of products started to decrease, but it was replaced by sugars and sodium. The problem there is that sugars end up being converted into fats. When glucose is consumed, because it can be used by virtually all the cells in the body, almost none of it is converted to fats—unlike fructose, [of which] estimates say about 30 percent is converted to fats. Combine that with the different biochemical responses: glucose produces insulin, but with fructose the brain does not receive that insulin signal and therefore, biochemically, one is still in starvation mode.”
According to De La Fuente, this problem is further complicated by the fact that nearly all of the U.S.-produced corn and soy are genetically modified organisms (GMO) that have been engineered specifically to resist or tolerate pesticides and to improve certain characteristics. “The vast majority of the corn used to produce HFCS is not suitable for human consumption in its whole form,” she explains. “It’s both engineered to withstand the application of pesticides, which the plant then absorbs (you are what you eat), as well as to yield higher starch percentages. Food manufacturers then use this ‘inedible’ crop to produce the seemingly endless volumes of ‘junk food’ sitting on shelves.”
The Consumption Conundrum
According to Meiggs, if Americans were actually consuming a natural diet from regular allowances of fruits and vegetables, then approximately 15 grams of fructose would be consumed in a given day. And when extrapolated to an entire year, this amount has been calculated to be about 12 pounds of fructose per year.
“Unfortunately, the statistics published now are saying that we actually consume about 60 pounds of fructose per year,” she says, “because we’re eating the wrong things, which speaks to the fact that it’s in your processed foods everywhere. This is really unfortunate because it’s extremely difficult to avoid.”
The crux of this consumption conundrum, of course, really lies in the omnipresence of the processed foods in modern-day society. “Ultimately, if people were cooking for themselves and maintaining a healthier diet, as opposed to eating processed foods that have these compounds in them, that would be the easiest way to eliminate [these health problems]. But when you have households with both parents working, to come home and make dinner is a really great strain on time and everything, and so this is part of the reason people turn to processed foods, and it’s just really unfortunate that they have to be made with such ingredients.”
On a societal level, De La Fuente says the U.S. already has a system in place that’s charged with protecting the public safety, and through this system, she believes opportunities exist for the government to create innovative ways of advancing nutrition education, with funding from taxes paid by companies that produce refined products. “Only a bold approach,” she adds, “will markedly shift consumers away from over-consuming refined sweeteners, because they are, in a word, ubiquitous, and we, as a society, love them.”
Demetrius, too, admits that the question of finding an answer to this predicament is an incredibly complex situation because HFCS is the cheapest way of sweetening products. And because it’s so concentrated that it can be diluted many times over and used for large quantities of beverages, the food industry is partial to using it because it can be such a high-profit margin with just a small amount of overhead. “People just have to be educated that they’re consuming lots of calories for the sweet products that they enjoy,” she explains. “They need to try and have more natural sources for those sweet drinks, meaning fruit juice or consuming the fruits themselves. But they also need to try enjoying other foods and fruits with equally enjoyable flavors, instead of going to such a highly concentrated sugar source.”
On the other hand, Demetrius says people will likely be best served by reducing their overall intake of processed foods. “Preferably, I do believe that people need to use organic foods when and where they can,” she says. “And also, consumers need to have more control over their own supply of food by supporting local farmers, and also—in whatever capacity they can plant their own foods and vegetables—so they can have complete control over what they put in, and what they treat their foods with.”
In the end, Meiggs too says she believes society will be best served by a more conscientious approach to food overall. “We cannot just point our fingers at fructose,” she says. “This is a far more wide-spread problem.”