Debunking Sugar Is Toxic & Other Myths

Douglas J. Peckenpaugh, Community Director of Content/Culinary Editor

Each year, the Experimental Biology conference draws members of the scientific community togetherincluding those from the health and nutrition sectorto explore the latest and greatest findings in the name of science. Last Sunday, April 22, 2012, at Experimental Biology 2012 in San Diego, one of the sessions, Fructose, Sucrose and High-Fructose Corn Syrup: Relevant Scientific Findings and Health Implications, resolutely debunked two sweetener mythsone rather dated myth that continues to linger in the mind of the general population regarding any scientific differences between the metabolic activity of high-fructose corn syrup (HFCS) and sugar, and another piece of misinformation that has begun recirculating as a result of recent national television coverage, namely that sugar is toxic.

HFCS = Sugar

A primary thrust of this Experimental Biology session was to analyze the established and emerging scientific evidence regarding the metabolic effects of HFCS, sucrose and fructose to determine if fructose is truly a metabolic danger or if it is simply a distraction impeding more potentially fruitful areas of scientific research related to the causes of hypertension, diabetes and metabolic syndrome. The session was sponsored by the prestigious American Society for Nutrition, one of the member societies in the Federation of American Societies for Experimental Biology.

The intent of this symposium was to give this very distinguished audience the latest scientific information on these three sugars: sucrose, high-fructose corn syrup, and fructose, says Dr. James Rippe, cardiologist, founder, Rippe Lifestyle Institute, and one of the symposiums invited speakers. There is a lot of controversy and a lot of misinformation and confusion related to those three sugars. A lot of people dont know that high-fructose corn syrup and sucrose are basically the same in terms of their composition. Theyre both about half fructose and half glucose.

Sucrose is comprised of half glucose and half fructose, while HFCS comes in different ratios: HFCS 55, which is 55% fructose and 45% glucose; HFCS 42 is 42% fructose and 58% glucose. Fructose is simply 100% fructose.

But a lot of people are confused about that, says Rippe. So we thought this would be a great time to bring together, for a debate, some of the people who have been very vocal in terms of their comments about the three sugars and express what the current science shows.

The symposiums first speaker was John White, Ph.D., a sugar biochemist, founder and president, White Technical Research. He laid out in great detail the equivalence of high-fructose corn syrup and sucrose and reminded us all that we dont consume fructose by itself in our diet, basically, for all intents and purposes, says Rippe. We always consume it as fructose and glucose, a vital consideration to factor into studies on the metabolic impact of fructose. He gave a lot of detail about the metabolism of sucrose and high-fructose corn syrup and contrasted it with some of the studies that have been done with pure fructose vs. pure glucose, which we dont consume in any appreciable degree.

Another speaker, Dr. George Bray, is chief of the Division of Clinical Obesity and Metabolism, Pennington Biomedical Research Center. He has been very vocal in his belief that sugar-sweetened beverages, whether sweetened with sucrose, which is the prevalent sweetener around the world, or high-fructose corn syrup, which is the prevalent sweetener in beverages in the United States, are a significant factor in the obesity epidemic that we have in the United States, says Rippe. However, he notes, Bray bases that argument largely on epidemiologic studiesstudies of large population groupswhich he acknowledged do not establish cause and effect.

They key here is to make sure that the parameters used as guidelines in the research match those present in real-life dietary situationsthat any conclusions are following logical, scientifically proven channels of cause and effect. If not, that enters a shadow of doubt on any of the studys findings.

During the session, Rippe presented findings from recent randomized, controlled trials, which are the highest level of evidence that you can have, he notes, on what we really know about sucrose and high-fructose corn syrup. I presented five different studies that basically all come to the same conclusion that various levels of consumption of either high-fructose corn syrup or sucrose are absolutely identical in terms of their metabolism and health effects.

This body of research comparing HFCS and sucrose included both acute studiesstudies done within a narrow time window, which Rippe notes are conducted in his facilitys metabolic unitand studies that take place over a more-extended period of time, and usually 10 to 12 weeks. Weve done a series of studies at dosage ranges anywhere from 8% of calories to 30% of calories, and that represents anywhere from the 25th to the 90th percent of population consumption levels of these sugars, he says. And we have found no adverse health consequences at any level, up to the 90th percent levelwith no differences between the 25th percent level and the 90th percent level, and no differences between high-fructose corn syrup and sucrose at any dosage level. There were no adverse health consequences at any of those normally consumed dosage levels. (References for this body of research are listed at the end of this article.)

So we have very compelling evidence now that really locks down even further that there is no difference between high-fructose corn syrup and sucrose, Rippe continues. So people in the food industry, companies that are substituting sucrose for high-fructose corn syrup, are doing so 100% for marketing purposes. From the medical health consequences from the standpoint of metabolism, the two are identical. Within the scientific community, there is no longer any debate that there is any difference between high-fructose corn syrup and sucrose.

Toxic Misinterpretations

Dr. Robert Lustig, professor of clinical pediatrics, Division of Endocrinology, and director, Weight Assessment for Teen and Child Health (WATCH) Program, University of California, San Francisco (UCSF), has, for some time now, been putting forth his theory that sugar, at high levelsostensibly reachable via some peoples daily dietshits the point of toxicity, causing the liver to convert sugar to fat, and subsequently plays a major factor in increasing risk of heart disease, as well as obesity, type 2 diabetes and hypertension. He claims that 75% of these conditions are preventable, and lumps sugar into the same category with alcohol and tobacco. (Lustig gained prominence primarily via his 2009 lecture, Sugar: The Bitter Truth, part of the UCSF Osher Center for Integrative Medicine series, Mini Medical School for the Public, which went viral on YouTube; his beliefs were also central to the 60 Minutes episode, Sugar, which aired on April 1, 2012.)

He has been a very vocal critic of sugar, in general, and has stated on national television and on YouTube that sugar is toxicthat its a major contributor to a variety of metabolic diseases all the way from obesity to heart disease and diabetes and cancer, even, says Rippe.

I presented a lot of science to dispute a number of the assertions that Dr. Lustig has made about sugar and sugar-sweetened beverages, says Rippe. Dr. Lustig maintains that sugars are turned into fat in the liver. And that simply is a misinterpretation of a lot of other peoples work. I pointed that out in detail. I talked to all of the key people whose work he referred to, and hes just misinterpreting their work. Yes, it is possible, if you give a lot of sugar, or a lot of fructose, to have the liver make a little bit of fat, maybe 1% of what we consume every day. But to maintain that in any appreciable way sugar is turned into fat is simply a misunderstanding of this research. And that is very clear from the viewpoint of the people who have done the research.

The final speaker in the symposium was David Klurfeld, Ph.D., national program leader, Human Nutrition, USDA-ARS. He basically said sugar is not toxic, says Rippe, and its silly to blame sugar for the obesity epidemic. He mentions that any substance, even water, can create adverse health consequences if given in excess. That doesnt make them toxic.

During his discussion, Klurfeld also statedin reference to Brays arguments regarding sweetened beverages and their role as a significant factor in the obesity crisis in this countrythat the regulatory bodies at USDA dont make decisions based on epidemiologic studies. They require prospective, persuasive, randomized, controlled trials, says Rippe.

References Provided by Dr. James Rippe

Lowndes J, Melanson K, Angelopoulos T, Rippe J. Does High Corn Syrup Affect Appetite or ad Libitum Energy Intake? (presented, Endocrine Society, 2009).

Lowndes J, Melanson K, Angelopoulos T, Rippe J. Does High Corn Syrup Affect Glucose or Hormones Affecting Appetite? (presented, Endocrine Society, 2009).

Melanson K, Zukley L, Lowndes J, Nguyen V, Angelopoulos T, Rippe J. Effects of High Fructose Corn Syrup and Sucrose Consumption on Circulating Glucose, Insulin, Leptin, and Ghrelin and on Appetite in Normal-Weight Women, Nutrition, Feb. 2007; 23(2):103-112.

Zukley L, Lowndes J, Melanson K, Nguyen V, Angelopoulos TJ, Rippe JM. The Effect of High-Fructose Corn Syrup on Post-Prandial Lipemia in Normal Weight Females, (presented, Annual Endocrine Society Meeting, 2007).

Lowndes J, Zukley L, Nguyen V, Rippe JM. The Effect of High-Fructose Corn Syrup on Uric Acid Levels in Normal Weight Women, (presented, Annual Endocrine Society Meeting, 2007).

Lowndes J, Zukley L, Paul M, Nguyen V, Knapp D, Brosnahan J, Summers A, Alvarado R, Meade N, Knapp D, Angelopoulos T, Rippe J. Replacement of Sucrose with High-Fructose Corn Syrup Does Not Alter Ad Libitum Energy Intake, Obesity, Supplement, 2006; 14:A183.

Zukley L, Lowndes J, Nguyen V, Melanson K, Angelopoulos T, Rippe J. Does High Fructose Corn Syrup Affect Appetite? Journal of the American Dietetic Association, Supplement 2, 2006; 2(6): .

Lowndes J, Zukley L, Nguyen V, Angelopoulos T, Rippe J. The Effect of High-Fructose Corn Syrup on Uric Acid Levels in Obese Women, Obesity, Supplement, 2007; 15:498-P.

Zukley L, Lowndes J, Melanson K, Nguyen V, Angelopoulos TJ, Rippe JM. The Effect of High-Fructose Corn Syrup on Triglycerides in Obese Females, Obesity, Supplement, 2007; 15:500-P.

Melanson K, Angelopoulos T, Nguyen V, Zukley L, Lowndes J, Rippe J. High-Fructose Corn Syrup, Energy Intake, and Appetite Regulation, American Journal of Clinical Nutrition, Supplement, Dec. 2008; 88(6): 1738S, 2008.