Robyn Landis is a Seattle-based writer and educator who loves chocolate and has no intention of giving up cookies and cakes, at least in moderation. But when it comes to sodas and desserts sweetened with high-fructose corn syrup, she believes in abstinence, not moderation.
"High-fructose corn syrup is a really low quality, really cheap sugar," the 38-year-old Landis says dismissively. The syrup starts out as cornstarch, which is then made sweeter by converting some of its glucose to fructose; the more fructose in the end product, the sweeter it is. "It is not something our bodies should be dealing with. It's completely unnatural."
She also objects to the fact that high-fructose corn syrup turns up in unlikely places, such as ketchup, baby food and baked beans. "Even chocolate tastes more like sugar than chocolate when it is sweetened with high-fructose corn syrup," says Landis, who favors products sweetened with organic, unrefined cane sugar.
Natural food advocates such as Landis aren't the only ones zeroing in on high-fructose corn syrup. With waistlines expanding, the fattest and richest country in the world continues to look for nutritional scapegoats. Now that a high-fat diet is no longer our sole dietary demon, all varieties of sugar have made a comeback as logical culprits, as has the fast-food industry.
Last year, the bestselling "Fast Food Nation: The Dark Side of the All-American Meal" linked the obesity epidemic to "supersized" portions of fast food, including sodas.
This year, the subsidized corn industry is under attack in "Fat Land: How Americans Became the Fattest People in the World." Author Greg Critser points to high-fructose corn syrup as a villain because it enabled the food industry to increase portion sizes without sacrificing profits.
He also faults the sweetener for overloading the American diet with fructose. The "cornification" of the American diet, says Critser is "skewing the national metabolism toward fat storage."
Dr. George A. Bray, an obesity researcher and professor of medicine at Louisiana State University Medical Center, also singles out high-fructose corn syrup because the meteoric rise in its consumption closely parallels the jump in obesity rates. "Nothing else in the food supply does this. It's a very, very striking relationship."
In particular Bray cites the dramatic increase in soda sales, especially among young people, whose obesity rates have doubled in the last 30 years. According to a 2002 article in the American Journal of Clinical Nutrition, adolescents' milk consumption decreased by 36% from 1965 to 1996. During that same period, soft-drink consumption increased 287% in boys and 224% in girls. Children and adolescents are drinking twice as much soda as milk, even as they're not getting enough calcium -- a mineral that may affect the body's ability to regulate weight, Bray says.
The case against high-fructose corn syrup has been fueled by concerns that Americans are ingesting too much fructose. Ironically, fructose, which is also known as fruit sugar, was once considered a healthier, "more natural" alternative to sucrose, that is, old-fashioned table sugar, because of its presence in fruit. In addition, diabetics thought it was healthier for them because it does not raise insulin or blood sugar levels as high as glucose does.
However, animal studies and preliminary human studies have found that a high-fructose diet leads to some of the same health problems that are rampant among overweight Americans, including insulin resistance and elevated triglyceride levels, a marker for heart disease.
Unlike glucose, fructose is almost entirely metabolized in the liver. When fructose reaches the liver, says Dr. William J. Whelan, a biochemist at the University of Miami School of Medicine, "the liver goes bananas and stops everything else to metabolize the fructose."
And the fructose propels the liver into a fat-promoting mode by activating the formation of enzymes that lead to elevated levels of "bad" cholesterol and triglycerides.
Even the fact that fructose does not raise insulin levels as high as glucose could be a problem for those with appetite-control problems, according to a 2002 article in the American Journal of Clinical Nutrition. Eating fructose results not only in lower insulin levels but also lower leptin levels. Because both hormones are involved in appetite control, eating lots of fructose "could increase the likelihood of weight gain."
Such studies have prompted the American Diabetes Assn. to conclude that "large amounts of fructose may increase blood fat levels" and that "there is no reason to use large amounts of fructose" in place of sucrose.
But skeptics, including some of the scientists who did the studies, caution that the case against fructose is far from proved.
Rush to judgment?
Dr. John Bantle, a professor of medicine at the University of Minnesota at Minneapolis Medical School, whose 2000 study showed a 32% increase in the triglyceride levels of men fed lots of fructose for six weeks, agrees that fructose "is probably not a good nutrient to put into the food system in large amounts."
But Bantle wants no part of what he sees as a rush to judgment against fructose. "It seems fructose has come into vogue as the culprit of the moment. Fructose is not guilty, at least when it comes to obesity."
In fact, most nutrition experts says it's no healthier to shop at a gourmet bakery for apple pie sweetened with sucrose than it is to indulge in a mass-produced, frozen apple pie sweetened with high-fructose corn syrup.
"Nutrition 101: Sucrose is glucose plus fructose stuck together. Corn sweeteners are glucose and fructose separated. It is hard to imagine that it makes much difference physiologically," says Marion Nestle, chairwoman of the Department of Nutrition and Food Studies at New York University.
Not only do both high-fructose corn syrup and sucrose contain fructose, they contain them in comparable amounts. According to the Corn Refiners Assn., most of the high-fructose corn syrup sold in this country contains 42% or 55% fructose, which averages out to a 50% fructose content. Sucrose is also made up of 50% fructose.
Even the nation's "nutrition police," the Center for Science in the Public Interest, which rails against America's out-of-control sweet tooth, sees no reason to single out high-fructose corn syrup. The center's executive director, Michael Jacobson, says the fact that Americans got a lot fatter when they started eating and drinking sugar in the form of the syrup doesn't mean that it's to blame. "A correlation is not a causation," he said.
Whelan concedes the point. He notes that someone once famously and ludicrously correlated the rising salaries of Presbyterian ministers in Philadelphia with the price of rum in Jamaica. He also notes that Europe is suffering from an obesity epidemic, albeit not as pronounced as this country's, even though production of high-fructose corn syrup is severely restricted, not for health reasons but lest it compete with the sugar industry.
However, Whelan also believes it is a good idea to scrutinize the syrup more closely. "There isn't any doubt that obesity is on the rise, and it must be coming from somewhere. It didn't come from thin air." And, says Whelan: "We are sure as heck eating a lot of HFCS."
A heck of a lot is 62.4 pounds per person as of 2001, slightly less than the 64.7 pounds per person of refined sugar. That's an extraordinary number, given the fact that high-fructose corn syrup didn't even exist until the late 1960s, when Japanese scientists, using enzymes, figured out how to convert cornstarch into a liquid with enough sweet fructose to compete with sugar.
By the mid-'70s, the high-fructose corn syrup industry was flourishing with HFCS 42, which contains 42% fructose and is 92% as sweet as sugar. But it was the advent of a 55% fructose product that converted the soft-drink industry to formulas 100% sweetened with high-fructose corn syrup. According to a 1996 history of high-fructose corn syrup, published in the industry journal Corn Annual, HFCS 55 "broke the sweetness barrier" by offering for the first time a product as sweet as liquid sugar.
Critser says the big winners in the shift away from sugar were the soda industry, because the syrup was a cheaper and easier-to-use alternative for liquid sugar at a time of soaring sugar prices, and the federally subsidized corn industry, which found a lucrative use for surplus corn.
But Critser says Americans lost out nutritionally because they were soon presented with lots of cheap ways to satisfy their hankering for sweets. Soda servings grew to 32 ounces and then 64 ounces. By the mid-'80s, the number of new candy and snack products, which had been stable at 250 a year during the '60s and '70s, soared to 2,000 a year.
Some researchers are worried that the new concern over the syrup and fructose will spill over to fruit. "We don't want people to stop eating fruit," which contains fiber, phytochemicals, antioxidants and relatively little fructose, says Peter Havel, an associate researcher in the department of nutrition at UC Davis. On the other hand, Havel says, consumers should avoid excessive amounts of fruit juice because of its high-fructose content.
That's why Boulder, Colo., physician Ron Rosedale tells his patients that they can keep their prized juicers -- as long as they eat the pulp and throw away the juice, which he derides as "sugar water." But Rosedale departs from common medical wisdom and goes further, steering his patients away from fruit, except low-fructose, high-nutrient blueberries: "I'm so against fructose I tell them not to eat very much fruit."
A lifestyle issue too
Most health professionals, however, think Americans would do better to focus on cutting back their intake of all added sugars rather than parsing the differences among sugars. Says Dr. David Heber, director of the UCLA Center for Human Nutrition: "If you're having 15 grams of sugar, who cares whether it's high-fructose corn syrup or sucrose? It's too much sugar."
Others believe that there has been too much focus on sugars as villains in the obesity epidemic and not enough focus on our sedentary lifestyles. Maureen Storey, acting director of the Center for Food and Nutrition Policy at Virginia Tech in Alexandria, says, for example, that the connection between soda drinking and obesity has been overblown because the sugary drinks are "easy targets."
Storey says her research shows that children who drink sodas are no fatter than those who don't drink sodas: "There has been so much attention to food that we are getting lost in the rest of the story, which is physical activity and the lack of it."
Virginia-based diabetes educator Hope Warshaw, who is also a consultant to corporations offering diabetes and nutrition products, agrees that it isn't fair to single out one ingredient or one food. Neither does she believe that food-industry bashing is productive: "To me it's a calorie issue. The food industry does produce too many calories for every mouth, but you can close your mouth too."
That's great advice, but lots of Americans, who regularly flunk out of their diet and exercise regimens, complain that they can't follow it. And obesity researcher Bray does not think Americans' failure to keep off weight they lose is because they suddenly became weak-willed when obesity rates started their precipitous climb in the '80s: "It is unlikely that willpower suddenly died."
Increasingly, obesity researchers, who are slowly unraveling the complex mechanisms that regulate body weight, view obesity as a disease, not a result of failed willpower. Bray thinks more sophisticated drugs will eventually help Americans fight the disease. And he also hopes for a more sophisticated analysis of the American diet so that the food supply can be rejiggered -- perhaps fewer sugars and more weight-regulating calcium -- in a way that "unconsciously" helps Americans eat less, just as fluoride helps prevent cavities even for Americans who don't brush or floss enough.