Here's your proof.. the abstract followed by the peer reviewed paper in a major cancer journal. It seems to me the journalist did a good job of summarizing the article in layman's terms. Sorry, but I'll take the researchers' study on this issue over your opinion:
Fructose Induces Transketolase Flux to Promote Pancreatic Cancer Growth
In my defense, I didn't say the study was incorrect, nor promote my "opinion" over their study. I did question the scientific knowledge of the reporters. How about this headline: "Cancer cells
slurp up fructose, US study finds" (my emphasis). Boy, if you wanted to sell papers via hysteria, you couldn't have come up with a better headline. But I digress.
Thanks for the link to the study. The study proves that fructose promotes pancreatic cancer growth, but it's not clear that the growth is faster (in a laboratory setting) than with glucose (bear with me). It also says nothing about HFCS vs sucrose (more below).
I read the study, and it's interesting. Ignore "Materials and Methods" and skip to "Results". Pancreatic cancer cells metabolize fructose and glucose through different paths (not surprising), and the cells are more efficient at creating nucleic acids with fructose ("fructose was preferentially metabolized at 250% higher rates than glucose"). Yet, despite being more effective at synthesizing nucleic acids with fructose,
the tumor cells did not grow faster in fructose ("proliferative rates were similar in fructose- or glucose-treated cells"). These seem to me to be in conflict with each other, and that wasn't discussed (that I could see). I take this as, in a laboratory setting, pancreatic tumors grow equally fast under glucose and fructose, but the metabolic pathways are different.
But "in a laboratory setting" does not necessarily equal "in your body". There's an important point in the Discussion section: "Furthermore, in healthy volunteers, serum fructose level rose rapidly following ingestion of a liquid fructose and glucose load, and in contrast to glucose that quickly returned to fasting levels,
serum fructose remained elevated for >2 hours, suggesting that circulating human fructose levels are unregulated in comparison with the exquisite regulation of blood glucose." (my emphasis)
And that's probably the issue with pancreatic cancer. Glucose is metabolized throughout your body, so blood levels drop quickly. Fructose is metabolized a lot slower (in the liver), so it stays in the bloodstream a lot longer, feeding the pancreatic tumor. Not good. Again, "Laboratory setting" != "inside human body"
So back to my comment about "It also says nothing about HFCS vs sucrose" - Your body digests sucrose into glucose and fructose in the small intestine. One molecule of sucrose digests into one molecule of fructose and one of glucose. You can't infer from the study that HFCS causes pancreatic cancer and sucrose doesn't. The study looks at glucose and fructose in isolation. It doesn't look at how the sugars enter you bloodstream.
Here's some wild-assed, unscientific speculation on my part, which makes me suspect HFCS is somewhat worse than sugar (How much? Beats me):
- Sucrose digests into a 50/50 mix of fructose/glucose.
- HFCS 55 (used in soda) is 55/42 fructose/glucose mix, so you get slightly more fructose from HCFS soda than sugar (but HFCS 42 in baked goods has <50% fructose - maybe it's safer then sucrose?)
- I have no idea how fast the body split sucrose. There's some delay in your body's breakdown of sucrose, whereas HFCS is immediately absorbable. So maybe HFCS causes blood glucose and fructose levels to spike faster and higher? That's probably not good. Also, if sucrose metabolism is really slow, maybe fructose levels don't spike at all (if your liver's rate of metabolism equals or exceeds the sucrose rate of digestion).
Also, I still don't understand the science behind how sugars in fruit turn out to be OK.
Plus, there's a lot more research being done on this issue and a Google search will bring up more studies.
Honestly, it's hard to find any unbiased research. You have the soda/corn industry funding research on one side, and the sugar industry on the other. Then you have the Chicken Little/sky-is-falling/I-saw-on-the-news-that-fructose-is-bad-so-I-can't-feed-any-of-that-stuff-to-my-family-or-I'm-bad-parent websites.
Here's a couple that downplay the risk of HFCS vs sugar:
American Journal of Clinical Nutrition:
Straight talk about high-fructose corn syrup: what it is and what it ain't
NIH:
Sucrose, High-Fructose Corn Syrup, and Fructose, Their Metabolism and Potential Health Effects: What Do We Really Know?
I agree all sugar is bad (with the exception of whole fruit in moderation - not extracted juice) but some things are much worse than others, and if we are going for sweetness, why not go for less harm? I tell my kids to avoid HFCS because it's much worse than sugar, which is bad, and we read labels and buy sugar over HFCS. Of course, it's a free country, and people can eat and drink what they want, but a trip to Disneyland will tell you something is seriously wrong with our diets. We are the most obese society in the history of mankind and this is the first generation in modern history that won't outlive their parent's generation. I am not blaming it all on HFCS, of course, because there are a number of variables.
I am also in the camp that believes it's not the quantity of food we eat (within reason) but the types of food. If I cut out pasta, bread and potatoes, and eat a ton more vegetables, I lose weight. I am 6', 185 lbs (so a bit overweight) but if I didn't eat right, and exercise, I could easily be 250 lbs, within no time, just by eating the wrong foods for a while. I can easily gain 10 to 20 lbs when I go to an all-inclusive or on a cruise. I never starve myself though. I just eat more raw or steamed foods and lots of salads, take the dog on long walks, use my treadmill desk (that's the best thing I have ever bought aside from the Tesla) and I can keep my weight in check.
No argument here, although (personally) I wouldn't assume straight sugar is much healthier than HFCS. If you need sweetness, it's probably better than HFCS by some degree, but I wouldn't count on much.
On a completely different topic - I need to get me one of those treadmill desks. That's just brilliant.
But what do I know? I'm just some guy on an internet message board.:wink:
But it's not true according to research:
