|Comments on Friday 2 November 2007:|
|So, recently I've been thinking I would like to perform an experiment comparing the effects of High Fructose Corn Syrup (the sweetening agent in most soft drinks nowadays, also known as Glucose-Fructose Syrup) and Sugar (aka sucrose, pretty much, once it's as refined as it is in a soft drink) on the human body. It is often alleged that the increasing prevalence of HFCS is a significant contributor to obesity, and, by its defenders, it is often argued that it has pretty much the same ratio of glucose and fructose as sucrose breaks down into so it can't be different.|
Now, I personally agree that it does have pretty much the same ratio of glucose and fructose, but what I'm not sure about is: 1. whether sucrose breaks down entirely into D-fructose and D-glucose, the sort that the body absorbs, or if some part of it will break down into the L- forms, and 2. whether the fact that sucrose has to break down into glucose and fructose will reduce the impact on the body because the glucose and fructose will be introduced more slowly as a result.
So, I was thinking what experiment would I perform, and I think pretty much the simplest and most effective experiment would be to have a blood monitoring device watch levels of glucose, leptin and insulin in the subject's blood at small intervals for a time after the subject chugs a half pint of solution (glucose or HFCS). Then a week later, with the subject having fasted into the same initial state, do the same with the other solution. Repeat four or five times alternating to make sure previous experiments are not effecting later experiments (or if they are, to make it so you have enough results that you can compensate for the effect - ideally use two or more subjects drinking the opposite solutions.)
And then I was thinking "well, that monitoring hardware is pretty expensive even just for a glucose monitor, is there some way you can make money from this sort of study if you're not being sponsored to come up with a specific result?" And the only way I could think of that you might is to sell the result to whoever it favours (ie. HFCS people would buy your study if it shows they are not responsible for obesity, sugar people would buy it if it says HFCS is for lardasses.) So I went looking to see who the people are who would buy a study, and I found something. Oh yes, I found something.
I found the sort of studies that "The Corn Refiners Association" might buy (actually it was Pepsi that paid for this one). They are studies which say "These short-term results suggest that when fructose is consumed in the form of high fructose corn syrup, there are no differences in the metabolic effects compared to sucrose." And when I say the studies say that, I mean just that. They say it. They don't show it. On the contrary, the experiment results, despite being fudged into oblivion, say that HFCS is quite sharply different. Here is the PDF file of the study. (Pages 103-112 of something.)
First point of interest - on page 107, see the most legible graph of "no difference". The left two thirds of the graph are almost illegible like all the other graphs, obscured by a mass of error-margin bars, but you can just about follow the lines back from the legible part to see this "no difference". It's a "no difference" of a consistent 10-20% higher leptin level in the HFCS line. Consistent. The error margins might say "but it could be equal, honest", but that's for each individual measurement - there are 20 or so measurements there, and they all are 10-20% higher. That's no margin of error.
Second point of interest - in the experimental conditions the subjects are not consuming only the products in question. They are consuming 30% test product, and 70% "a normal diet". So one might infer from this that a 10-20% difference might be more like a 30-60% difference if we were comparing apples to oranges rather than comparing an apple and two bananas to an orange and two bananas. And you know what you really can't do with a 30-60% difference? Fudge it with error bars.
Point of interest 3 - the laughable table of data on page 108. The area under the curve. Just like the lines, the numbers (reflecting glucose, insulin and leptin) are all 10-20% higher with HFCS than with sucrose. But look at the numbers. HFCS area under the glucose curve = 144.83 ± 116.62. An error margin of 80%. Sucrose area under the glucose curve = 121.33 ± 135.67. An error margin of a staggering 112%. They're claiming they can't even tell whether the subject had reduced glucose from consuming sugars. Why? Because you need a huge margin of error to claim your correlation is not significant.
The actual experiment design is pretty good, but the "LA LA LA THE RESULTS SAY NOTHING" conclusion is just comical. Anyway, my personal conclusion is that I now don't feel the need to perform the experiment for myself, seeing as an experiment showing the results it was trying to avoid is usually a pretty reliable indicator of how things are. [17:29]
|You actually find this surprising?|
|Do I find what surprising?|
That people lie? No.
That they lie citing data so clearly contrary to what they're saying? A bit, yes, given that it would be just as easy to falsify data as to falsify a conclusion, and more convincing.
That there are many people who will vehemently argue that HFCS is no worse than sugar, presumably having believed the poorly-cited lies? No, not that either, really.
|I meant the underlying data that lead you to abandon your experiment.|
|Obviously I was pretty sure it was the case, or I'd not have had the interest in the experiment, but I didn't have any compelling evidence - only correlation and the word of unreliable sources. I didn't even have raw possibly-biased data saying so.|
I didn't expect to be able to find data that is so clearly unbiased (because if it had been biased it would have been biased the opposite way) without doing an experiment for myself.
|Hey there. Total random stranger here. :) I did a google search for vasectomies and I see in your archives (2004) that you had one with Vasectomy Service Carlton. I'm thinking of getting one and I was wondering if you could tell me what VSC was like? Were they professional, etc. Also, a rather personal question here: How is it affected your sex life and do you use any other birth control methods or has it been 100% successful?|
Thanks for your time :)
|Obviously I don't have multiple vasectomy experiences to compare, but VSC were fine as far as I was concerned. The mandatory "are you sure" conversation was as minimal as I'd have hoped, and the operation was over before I even knew it had begun. I though it was still anaesthetic.|
The only effects on sex life were 1. no sex for a week or so afterwards because it does hurt for about that long (two days of it just hurts, a week of hurts-if-you-poke-it), and 2. not needing condoms (when there's known to be no STDs obviously). It's been 100% successful.
|Cool! Thanks so much for your prompt reply. :)|
|PDF has moved to http://www.sweetsurprise.com/sites/default/files/MelansonNutritionFeb2007.pdf|
For the sake of being able to find it again if it moves, the study is:
Effects of high-fructose corn syrup and sucrose consumption on circulating glucose, insulin, leptin and ghrelin and on appetite in normal-weight women
Kathleen J. Melanson, Ph.D., R.D., L.D.
Linda Zukley, M.A., R.N.,
Joshua Lowndes, M.A.,
Von Nguyen, M.S., R.D.,
Theodore J. Angelopoulos, Ph.D., M.P.H.,
James M. Rippe, M.D.