Fructose: Evidence for Trouble with Your Liver

November 22, 2006

Fructose:  Evidence for Trouble with Your Liver 

 Competency # 11 Sugar and Fructose                    Reference: American Association for the Study of Liver Diseases Annual Meeting  Oct 26, 2006 Reported in:  Scientific American, Science News Nov 2006 

 Supersize me!  The movie already gave us this clue.  In the movie, the premise was that upon every visit to McDonald’s, the lead character had to take whatever was offered and if a size upgrade was offered, that had to be accepted.  Eating at McDonald's three times a day for a month almost killed Morgan Spurlock.  His liver became fatty and his liver function test results went through the roof. Not good. 

 Now, the American Association for the Study of Liver Disease (AASLD) annual meeting confirmed that this phenomenon was not just due to random chance.  Mice fed a diet of sweetened water made sweet from either pure glucose, fructose, sucrose, or saccharin gained weight in a predictable way.  The fructose mice got a condition called fatty liver or steatosis.  Just like in the movie, “Supersize Me.”  The researchers concluded that the mice with the fatty fructose liver had increased oxidative stress as the mechanism for their damaged liver. 

 In America, we have had an absolute increase in liver disease, and we have had trouble figuring out exactly where it came from.  We have accumulating evidence that reactive oxygen molecules cause trouble to many cells.  The mechanisms are beginning to be delineated.  Our mitochondria (the miniature power plants in our cells that manufacture energy for the rest of the cell) are damaged by oxidative stress.  Increasing calories set off that same response of oxidative stress and mitochondrial damage too.  Our biology makes eating sugar way too tempting.  We just can’t resist it because it just tastes so so good.  

Now, the evidence may be enough to start pointing a finger. Fructose in fruit seems to be fine.  Fructose is part of table sugar, or sucrose,  and high fructose corn syrup.  Coming in the form of HFCS (high fructose corn syrup), fructose gets concentrated past the 50/50 mark and seems to cause trouble.  Manufacturers know it’s cheaper by about a penny a can to make soda with HFCS rather than sucrose.  Fructose is cheap and corn, the substrate from which it’s made, is abundant.  Food processing companies like fructose because it’s also more stable and weighs less.  You get more bang for the buck. So does your liver. 

 WWW.  What Will Work for Me?  It’s time to call fructose a nutritional problem.  In the context of fruit, it seems to be ok.  There it comes wrapped in fiber, which helps us absorb it slowly.  But this is enough evidence for me to now add fructose to my list of why it’s worthwhile reading labels.  And friends don’t let friends eat fructose.  (Can you imagine going to McDonald's with me?  I would be impossible.)  

This column was written by Dr. John E. Whitcomb, MD, Brookfield Longevity, Brookfield, WI, (262-784-5300)