Fructose: Evil or Misunderstood?

By Mike Howard

Fructose, particularly in the form of high fructose corn syrup (HFCS), has been labelled the devil of all food creations. A video surfaced on youtube this past year by a well-spoken and clearly educated doctor by the name of Robert Lustig.

The video’s length would make James Cameron cringe, but it is a very detailed look into the science, politics and health effects of fructose. The video received some very positive accolades in the on-line and print community, with both lay people and industry professionals lauding Dr. Lustig, and his clear message: Fructose is Toxic.

A recent rebuttal to this video on a straight-shooting fitness and nutrition blog, has caused quite a heated discussion.

Let’s review the video and the rebuttal, and try and make some sense out of it all.

The Real Truth About High Fructose Corn Syrup

  • The amount of high fructose corn syrup (HFCS) has gone up 1000+% from 1970 to present day.
  • Too much fructose in the form of HFCS can in fact have some negative impacts on health.
  • Americans consume over 60lbs of HFCS annually, accounting for over 400 calories per day.
  • Fructose bi-passes the breakdown process that glucose undergoes and heads straight for the liver – theoretically making the liver work overtime to process it.
  • Dr. Lustig does a very good job of breaking down the politics on how we came to be eating so much HFCS (in short, it’s cheap).
  • He gives what looks to be a sound biochemical breakdown of how fructose acts on the liver, and the potential consequences of the body.
  • Lustig also acknowledges correctly that fructose is not an “acute toxin”, implying that there is a dose-response to fructose’s dangers.

Fructose: The Bitter (stretching of the) Truth

  • The alleged toxicity of fructose is context-dependant. Lustig does not mention any dose ranges, and claims that fructose is fattening irrespective of caloric intake.
  • Human studies to date have not found higher fructose intakes to be any more fattening than other sugars when calories are controlled.
  • The studies which do demonstrate adverse effects of fructose consumption are in unreasonably high doses.
  • Dr. Lustig points to fructose’s negative effects on hormones, particularly leptin. However, leptin impairment was found in rats consuming a diet of 60% fructose.
  • While it is convenient to point the finger at HFCS for the obesity epidemic, total calories went up markedly in that same time period.
  • In addition to fear-mongering, Dr. Lustig makes some statements in his video that range from curious to outrageous. For example, in his opening monologue, he states that “Japanese populations don’t eat fructose“. This is flat-out wrong, as it is estimated that the Japanese’s sugar consumption is about ¼ HFCS.
  • Another flaw in the HFCS-is-causing-obesity argument is that countries in Europe, Australia and Mexico have raising obesity rates, but do not have correspondingly high HFCS intake.

What To Do?

  • Referring to anything as a “toxin” warrants contextualization. Consuming HFCS in smaller amounts, within a calorically-reasonable diet, won’t do anything bad to you.
  • Eating a lot of something that has empty calories will pack on the pounds, and have health consequences. HFCS is no exception, but it certainly isn’t special.
  • There is no argument that too much of our food consumption is in the form of sugared foods and drinks. Cutting back on these will help reduce your waistline, and promote better health.
  • I can’t think of a single good reason to cut fruit out of your diet.


  1. Rodin J, Reed D, Jamner L. Metabolic effects of fructose and glucose: implications for food intake. Am J Clin Nutr. 1988 Apr;47(4):683-9.
  2. Moran TH. Fructose and satiety. J Nutr. 2009 Jun;139(6):1253S-1256S. Epub 2009 Apr 29.
  3. Teff KL, et al. Dietary fructose reduces circulating insulin and leptin, attenuates postprandial suppression of ghrelin, and increases triglycerides in women. J Clin Endocrinol Metab. 2004 Jun;89(6):2963-72.
  4. Livesy G. Fructose ingestion: dose-dependent responses in health research. J Nutr. 2009 Jun;139(6):1246S-1252S. Epub 2009 Apr 22.
  5. WHO Oral Health Country/Area Profile Programme


  1. Jim Carnicelli

    Lustig focuses his presentation on fructose, specifically. However, he does assert that it doesn’t matter if you are getting it from HFCS or sucrose (cane sugar) at the end, since it is one part glucose and one part fructose. You have to listen carefully for it.

    • Luanne Robalo

      It does matter. There is a distinction between HFCS and sugar. I have an MS in biochemistry and molecular biology and fructose was the topic of my masters studies. You can learn the science by visiting The video isn’t up yet but its coming.

  2. Hawkeye

    Agave “nectar” is a highly refined product which, depending on the manufacturer, is anywhere from 55% to 97% fructose. HFCS is only 55% fructose. Agave, therefore, is somewhere between “at least as bad” to “much worse than” HFCS. White table sugar is healthier.

    For information about stevia:

  3. V.A.

    Like Michael G., I would very much like to know the chemical make-up of and physiological response to Stevia and agave nectar. Many of my friends are quite convinced that Agave is the best sweetener available.

    I agree with Chris and would add that he did not state that “Japanese populations don’t eat fructose”. He was comparing the “Atkins Diet” and the “Japanese Diet” (trendy diets). He did say that their commonality is “eliminating fructose” which is an obvious exaggeration. The later stages of Atkins allow for fruit and the Japanese Diet allows fruits and very small portions of rich desserts. I think his point (though maybe not well presented) was to establish his hypothesis at the beginning in a creative way with references to commonly known diet fads. It was clear from his presentation that he did not actually suggest completely eliminating fructose in fruit from a healthy diet.

    There may be factual issues with the presentation. I am very anxious to know the truth concerning the effects of fructose, in all it’s forms, in the body, whatever that truth may be. More research needs to be done in this area. Scientific studies are interpreted too broadly _most_ of the time. I will be axious to see what comes of this line of research.

  4. V.A.

    This is not a republican issue. There are plenty of democratic farmers in the midwest area in which I grew up!

  5. Chris R.

    Hey found this page and wanted to point something out. This post seams to concentrate on HFCS, Lustig did not, he did even point that that he agreed that HFCS was just as healthy as regular sugar. He also agreed that the issue was also a volume problem, and that fructose was processed the same as ethonal (alcohol) but fructose did not have the same guards as ethonal because it was not an acute toxin like ethonal is.

    I’m not going to rehash the previous comment but will add that Lustig makes a point that every time you find fructose in nature it’s paired with fiber, thus why fruits are not a problem to him.

    one section he did spend a lot time on was pointing out was not all calories are equal, some calories do not send the proper signals to the brain telling it to stop. This was the very detailed break down of how the body processes fructose vs ethanol vs sugar.

    • Pamela White

      Thank you – most all of what you said was what I was going to say after reading the first four comments. One must follow the presentation closely.

    • Luanne Robalo

      What is overlooked by most especially HFCS supporters is the plight of fructose malabsorbers. Scientific estimates are that more than 30% of adults and more than 45% of kids don’t absorb it well. What has also been overlooked in scientific research is what is happening in the intestines of these people because fructose is known to be 10 times more reactive than glucose. Get the facts at It has a ton of links to scientific articles on fructose. It’s a new site and the video isn’t up yet. But it is very informative

  6. Michael G.

    “I can’t think of a single good reason to cut fruit out of your diet.”

    What a throw-away comment… Nobody in the video “Sugar, The Bitter Truth” suggested removing fruit from the diet. In fact, as I recall, the presenter specifically said fruit was GOOD to keep in the diet due to the fact it is generally a much lower “dose” of fructose. It’s not “high fructose” (aka, artificially distilled and concentrated). Plus it has vitamins, minerals water and fiber that is stripped out when concentrating HFCS.

    I hate that everyone seem to throw out that stupid red herring. It’s like they didn’t even bother to WATCH the video before criticizing it.

    The major point of the video is that HFCS is an ARTIFICIAL CONCENTRATION of fructose that removes the other nutritive values of the foods it would otherwise be found in (aka, fruits & vegetables) and it has found its way into every nook and cranny of our food supply: I dare you to look through the bread aisle of any major grocery store and fine more than one or two brands without it. And usually those brands are much more expensive (due to the extreme cheapness and ubiquity of HFCS).Like I said, it’s made its way into everything: candy, bread, hamburger & hot dog buns, the catsup that goes on the hamburgers, cereal, just about all cola, fruit “drinks”/”cocktails” (not to be confused with “juice”), baby formula.

    It’s this over-saturation of the market with HFCS that is claimed to be the problem. Nearly everything we eat these days has the stuff in it. And that’s the problem. Sure, any ONE item maybe doesn’t have the 60% fructose diet that was fed to rats. But that doesn’t mean that when you total it all up, day in and day out, week in and week out, we’re not eating WAY too much of the stuff.

    That’s the issue in a nutshell. It’s in EVERYthing (more or less) and the effect, as you say, is not acute. It’s chronic. It’s a CUMULATIVE effect.

    It barely gets used by the body, it doesn’t signal/trigger the brain on satiety, so we keep eating rather than stopping. The excess is processed by the liver into fatty deposits, raised “bad” cholesterol and triglyceride levels.

    as an aside, I wonder if anyone has studied the biochemical interaction of sugars like agave and stevia with the body. What’s their chemical makeup? Do they have similar negative interactions with the body to those of fructose (not satisfying the satiety signal, being processed by the liver, causing fatty deposits or raised cholesterol/triglycerides)? If not, it might be interesting to see how the body reacts to them over time and if they might supplement our need for sweeteners while mitigating the apparent negative effects of fructose…

  7. Ryan

    Also, the fructose in HFCS is of different structure than the fructose in fruit. Some people make the distinction that the fructose in fruit or honey should actually be called “L-fructose” or “levulose”, and the fructose in HFCS should be called “D-fructose”.

  8. ps

    The same farmers who vote republican and want government off their backs… but want the feds to keep sending $$$

  9. Spectra

    I see no issues with naturally occurring fructose in your diet, mostly because fructose in nature is found in fruits/veggies which have fiber and water in them as well. So that helps slow the absorption of it into your body. When you ADD fructose to just about everything under the sun (like ketchup, sauces, soda, etc.), that’s when you have to worry. That’s where you get the calorie overload and the problems with diabetes.

  10. J. Foster

    Trade protectionism I guess. US & EU are very protective of the agricultural industries, despite the fact that it goes against the much-lauded principles of free market capitalism.

    In 2004 $2.84 billion was paid out to farmers for growing corn… So we end up with low global prices (devastating to the developing nations in the world), and an oversupply of certain foods… so… we get fat and pay lots more taxes…

  11. Barry

    Sort of begs the question. Why are corn growers being subsidized?

  12. J. Foster

    Good work Mike. To be honest the HFCS issue tightly tied to subsidies and trade issues (As PS implies above). Until the US stops the phenomenal subsidizing of certain agricultural crops (as the EU does), then HFCS is going to be a favored sweetener.

  13. PS

    I’m sure the subsidized corn farmers, ADM and Cargil will go on the assault. Maybe toxic is stretching it, the lifestyle impact has been Toxic. Look at obesity, diabetes and amputations (that we the taxpayers subsidize or pay for outright). Tax it and regulate it. And for our midwest welfare recipients of farm subsidies, I’m sure we’ll be hearing from you.

  14. Lana

    Thank you for breaking this down for me!