Sugar is Sugar is Sugar  —  Part 2 – Watts Up With That?

Considering that High Fructose Corn Syrup (HFCS) is just sugar water, with a similar composition to table sugar, why is it vilified?

# # # # #

Villainizing HFCS is an outgrowth of the more general War on Sugar. Acting under the pretense (or misunderstanding) that HFCS is “high” in fructose, a great deal of research has been carried out to study the results of feeding 100% fructose to animals and people. 

“Although the HFCS-obesity hypothesis may have been initially developed, as Popkin recently claimed, to simply “spur science” (link), it quickly took on a life of its own. This once mundane ingredient became vilified in scientific circles and then in the public arena when the hypothesis was translated as fact through leading nutrition journals, weekly and specialty magazines, national and local newspapers, and an endless number of television news programs.” [ source ]

Barry Popkin, a co-author of the study mentioned above, rapidly back-pedaled on the hypothesis:

“Even the two scientists who first propagated the idea of a unique link between high-fructose corn syrup and America’s soaring obesity rates have gently backed off from their initial theories. Barry M. Popkin, a nutrition professor at the University of North Carolina at Chapel Hill, says that a widely read paper on the subject that he wrote in 2004 with George A. Bray, a professor of medicine at the Pennington Biomedical Research Center in Baton Rouge, La., was just meant to be a “suggestion” that would inspire further study.” …..  “It was a theory meant to spur science, but it’s quite possible that it may be found out not to be true,” Professor Popkin said. “I don’t think there should be a perception that high-fructose corn syrup has caused obesity until we know more.” “[ source ]

Robert F. Kennedy Jr. is the current U.S. Federal government’s Secretary of Health and Human Services, with control over the Centers for Disease Control and Prevention (CDC), the National Institutes of Health (NIH), the Food and Drug Administration (FDA), and the Centers for Medicare & Medicaid Services (CMS).

Robert F. Kennedy Jr. said, in 2024:   High-fructose corn syrup ‘is just a formula for making you obese and diabetic.’” [ source ]  

This opinion depends on the large body of research that has studied the metabolic differences between diets contain exclusively fructose compared to diets containing exclusively glucose.

“If the HFCS-obesity hypothesis is correct, there should be something quantifiably unique about HFCS that is absent from sucrose. The data presented thus far in support of the hypothesis rely heavily on the metabolic comparison of glucose and fructose. It has been known for many years that fructose fed to experimental animals or human subjects in high concentration (up to 35% of calories) and in the absence of any dietary glucose will produce metabolic anomalies (7,8). The 1994 Fructose Nutrition Review commissioned by the International Life Sciences Institute was highly critical of this line of experimentation (29 – Hollenbeck (1993)).” [source]

In fact, the 1994 review mentioned concluded, among other things:

“These conclusions should not be interpreted as an admonishment to restrict all dietary fructose. Indeed, fructose is an important natural component in our diet, and an abundant source of carbohydrate in fruits and vegetables. Although the term “reasonable quantities” would be difficult to define quantitatively, it would seem unlikely, based on available data, that dietary fructose at quantities obtainable from natural sources provided in a well-balanced diet would result in any deleterious metabolic effects.” [ source ]

A diet high in fructose, in the absence of glucose, “will produce metabolic anomalies”.  But neither a diet containing sucrose or HFCS lacks the necessary glucose to produce those metabolic anomalies….both sucrose and HFCS are approximately the same:  50% glucose and 50% fructose.

In Part 1 of this essay, I showed this image from Bray et al (2004):

And I asked readers if they could see what had been omitted from the graph.  The following graph answers that question:

The data is from differing sources but close enough for our comparison.  Bray et al. gives estimated intakes of “total fructose” and “free fructose”, against U.S. overweight and obesity rates. Total fructose means all the fructose from sucrose (which is one half fructose) plus all the fructose from fruits plus all the fructose from HFCS (which is shown as “free fructose”, which is about one half the total sugar in HFCS). 

What is omitted from that graph is any change in the intake of Total Sugars.  The first graph  (Bray) seems to imply that total sugar intake has risen, but as given in the second graph as “percentage of caloric intake”, which, at least in that view, doesn’t really change much.

In this graph, we see that total sugar intake (not total fructose)  increased by about 17% from 1970 to 2005, which is not quite in agreement with previous graph, which shows a 1% increase in calories from added sugars over the same time period.  Again, the difference may be entirely due to the difference in method of calculation (What Exactly Are they Counting, and here).  But the point of this is that the decrease in the amount of cane and beet sugar in U.S. diets were almost one-for-one replaced by the increase in HFCS between 1970 and 2005, and since then are about even.   Over the same time period, grains (flour and cereals) and fats increased.

Further, U.S. domestic use of HFCS hit a high point in 2001 and has been declining since, while U.S. obesity rates have continued to climb:

Is the increase in the use of HFCS causing Overweight and Obesity?

Let’s see:

One thing to know is that the goal posts were moved for overweight and obesity in 1998:

The BMI classifications for overweight were changed in 1998 by the National Institutes of Health (NIH). The NIH adopted the World Health Organization’s (WHO) classification, lowering  the threshold for overweight from a BMI of 27.8 (men) / 27.3 (women) to a BMI of 25. This change effectively reclassified millions of Americans as overweight or obese.  Thus, any historical calculation of Overweight/Obesity must include if the older data (in the pre-1998 time frame ) was determined by the then current standard or the new post-1998 standard.  

Taking an international viewpoint, we can see with this graph that HFCS consumption on a national basis is not predictive of overweight and obesity:

Examples of pure fructose causing metabolic upset at high concentrations are common, especially when fed as the sole carbohydrate source, however there is no evidence that the common fructose-glucose sweeteners – sucrose, HFCS42, HFCS 55, honey – do the same.

Again, this does not mean that large increases in intake of sweeteners and other high caloric foods do not affect overweight and obesity – but it does mean that increased HFCS use in foods and drinks does not equate to increasing overweight and obesity rates.

Another common claim is that because HFCS is a liquid and used in drinks (sodas, sports drinks, etc) it causes more weight gain than solid sugars.   This oft repeated view is based mostly on a single small human study, DiMeglio and Mattes (2000) [ pdf ]:

“The study investigated the difference between two forms of carbohydrate delivery:

1. Liquid form: The carbohydrate load was delivered as calorically sweetened soda for a duration of four weeks.
2. Solid form: The same carbohydrate load was delivered as jelly beans for a separate four-week period. 

The researchers observed that when the carbohydrate load was consumed as soda, the participants experienced significantly greater weight gain compared to when the same amount of carbohydrate was consumed as jelly beans.”

When I say “small study”, I mean really small: only 15 people.  Participants were offered sweet sodas for four weeks then jelly beans for 4 weeks, in addition to their otherwise normal daily diets.  It certainly tested something, but not whether liquid or solid sweeteners caused more weight gain.  Here is the graphical data summary claiming to show “significantly greater weight gain” for liquid (soda) sugar (with my notations):

­[ Click for larger image ]

All the other studies on this topic are mice and rat studies. Why this matters is discussed here and here (and many, many more).

Important Note:  The innocence of HFCS as a unique or special cause of overweight and obesity does not mean that excessive over-consumption of high caloric foods (sugars, starches, fats) does not contribute to those conditions.  It is simply that HFCS does not do so in any special way.

IN SUMMARY:

For HFCS to be somehow especially obesogenic (causing obesity), it would have to differ from sucrose in an important way.  However, HFCS is essentially the same as sucrose.

If HFCS was uniquely obesogenic, HFCS usage and obesity would be coincident nationally and internationally.   They are not.  In the U.S., HFCS use has declined almost 20% over the last two decades while obesity rates continue to rise.  

Diabetes is related to obesity, with obesity being particularly considered a contributing cause of Diabetes Type II.  As HFCS itself is not a particular cause of obesity, any more than any other sugar, it is probably not a cause of diabetes.  There is no evidence that HFCS ingestion causes diabetes of either type.

Despite the popular health press and notwithstanding Robert F. Kennedy Jr.’s opinion, the U.S. Food and Drug Administration still says:

“We are not aware of any evidence, including the studies mentioned above, that there is a difference in safety between foods containing HFCS 42 or HFCS 55 and foods containing similar amounts of other nutritive sweeteners with approximately equal glucose and fructose content, such as sucrose, honey, or other traditional sweeteners.”  [ source ]

# # # # #

Author’s Comment:

I am not aware of any real evidence that HFCS is in any way more or less harmful or beneficial than any other glucose/fructose caloric sweetener.  Nor is the FDA. 

There are a lot of arguments based on half-understood science, but no real evidence.   

HFCS is, in my opinion, simply being scapegoated based on the long-term War on Sugar, andmaybe just based on the misunderstanding of its name: High-fructose corn syrup. (see Propter nomen) 

Please, this essay is not about The Obesity Epidemic.  It is about HFCS.

Thanks for reading.

# # # # #

Related