The "Skinny" On High-Fructose Corn Syrup
March 15, 2011 by Dr. Mark Wiley
If you’re like me, you’ve heard a great deal of conflicting talk about the naturalness, goodness, badness, healthfulness and harmfulness of high fructose corn syrup (HFCS).
The FDA says it can be labeled a “natural” product because it is made from corn. Yet, a percentage of the corn it is manufactured from is known as GMO or has been genetically modified. That doesn’t sound so natural to me.
The corn people tell us that HFCS is the same as sugar and is healthy in moderation. Yet, HFCS is much sweeter than regular table sugar or the sugars found in fruit. So the definition of what is “in moderation” for HFCS is different than that for white processed sugar. They neglected to tell us that.
There has been a good deal of noise about HFCS being responsible, in part, for the current rise in childhood obesity. After all, HFCS has replaced sugar in a large number of packaged foods and beverages kids (and adults) consume on a daily basis.
A study presented at the American Society of Nephrology’s 42nd Annual Meeting found that the rate of obesity has increased sharply since the development of HFCS and that the prevalence of HFCS in processed foods may have something to do with it. It’s been reported that Americans now consume 30 percent more fructose than they did 20 years ago.
Yet, the website sweetsurprise.com claims that high fructose corn syrup does not contribute to obesity any differently than sugar. In support of this assertion they quote from a 2007 study:
“An expert panel, led by Richard Forshee, Ph.D. of the University of Maryland Center for Food, Nutrition and Agriculture Policy, concluded that “the currently available evidence is insufficient to implicate high fructose corn syrup per se as a causal factor in the overweight and obesity problem in the United States.” The panel’s report was published in the August 2007 issue of Critical Reviews in Food Science and Nutrition.”
Hmmm. We all know that studies are designed in different ways and that their results can often be spoken of in a way that supports opposing claims. But a visual assessment of childhood obesity and even obesity among the college-age population shows weight is on the rise. A peek at the ingredient labels shows a definite move from sucrose and fructose to high fructose corn syrup. But correlation does always indicate causation.
The question is, is there science behind how the body breaks down and responds to HFCS versus sucrose or fructose? The answer is, yes.
In the March 2011 issue of Diabetes, Obesity, and Metabolism it was shown that cortical control areas in the brain responded differently to the infusion of fructose than they did to glucose.
“BOLD signal decreased in the cortical control areas during fructose infusion (p = 0.006), corresponding with increases of plasma fructose and lactate. Neither glucose nor fructose infusions significantly altered BOLD signal in the hypothalamus.”
The cortical control areas surround the hypothalamus which is a key player in appetite levels and control of metabolic hormone production.
In essence, glucose and fructose are both simple sugars. Yet the body does not process them in the same way. In 2002, the Department of Nutrition at the University of California—Davis conducted a study on fructose, weight gain and the insulin resistance syndrome. Here is part of the abstract:
“Because fructose does not stimulate insulin secretion from pancreatic ß cells, the consumption of foods and beverages containing fructose produces smaller postprandial insulin excursions than does consumption of glucose-containing carbohydrate. Because leptin production is regulated by insulin responses to meals, fructose consumption also reduces circulating leptin concentrations. The combined effects of lowered circulating leptin and insulin in individuals who consume diets that are high in dietary fructose could therefore increase the likelihood of weight gain and its associated metabolic sequelae.”
What’s more, in a large 2009 study looking at the connection between HFCS and hypertension, Diana Jalal and colleagues from the University of Colorado Health Sciences Center recruited nearly 4,600 adults over the age of 18. They found that individuals who consumed more than 72 grams of fructose each day were between 26 percent and 77 percent (depending upon the blood pressure threshold) more likely to be hypertensive than those who eat few foods containing added sugar.
These studies do not show HFCS in the same light as being “just the same as sugar.” In the wake of all this hoopla, Snapple beverages have discontinued their use of high fructose corn syrup and have returned to the use of sugar in their iced tea and other fruit flavored drinks.
It would be a safe bet for all of us to read the labels and choose healthier options. Where sugar is the ‘healthier’ option, of course it is just a distinction between the lesser of two evils.
–Dr. Mark Wiley
References: American Journal of Clinical Nutrition, Vol. 76, No. 5, 911-922, November 2002
Diabetes, Obesity, and Metabolism March 2011; 13(3): 229-234 http://onlinelibrary.wiley.com/doi/10.1111/j.1463-1326.2010.01340.x/abstract
American Journal of Clinical Nutrition, Vol. 76, No. 5, 911-922, November 2002