Fructose and Nonalcoholic fatty liver disease (NAFLD)
Well I’ve been slacking lately. Work has been pretty busy so I haven’t been able to keep up with my posts as of late. For those of you reading, I apologize!
I thought I would start up again with an interesting study published in Nature (a huge scientific journal) in May about the role of high fructose corn syrup and liver disease, specifically, Nonalcoholic fatty liver disease (NAFLD). In NAFLD, the “two hit theory” is currently the postulated mechanism and goes as follows (rough summation using fructose):
1) Liver metabolism of fructose causes fat synthesis from scratch, inhibition of fat breakdown, a movement towards insulin resistance, and hyperglycemia (high blood sugar)
2) Due to the instability of fructose (a 5-carbon ring), it causes the formation of what are called Reactive Oxygen species (ROS), which both use up your antioxidant stores and cause inflammation if one doesn’t have enough antioxidants. Given High fructose corn syrup (HFCS) is in many cheap foods, many individuals consuming such a high amount of HFCS are generally lacking in many nutrients.
So in this paper, the authors postulate that the high levels of HFCS in the western diet contribute to the pathogenesis of NAFLD. The main data they use to show this is using ALT levels (may have heard this while watching house - a liver enzyme which indicates stress) increasing in obese children with the increase in calories of sweetened soft drinks, which contain high levels of HFCS. It seems that as the children increase their consumption of sugary drinks, their ALT levels rise (liver is more stressed).
I think this is very interesting given the small, small difference in HFCS vs sucrose (table sugar). HFCS is 55% fructose and 45% glucose, whereas table sugar is 50/50! Only a 5% difference! However, surely small differences can add up over time and cause larger, summation type of effects. It’s nearly impossible to avoid this stuff, but I suppose this may make us think twice before we down our bottomless cokes!
What do you think of this? See the link below for more details.
Source: Nature Gastroenterology and Hepatology
http://www.nature.com/nrgastro/journal/v7/n5/full/nrgastro.2010.41.html
(PS: I can’t get my picture to work at the moment, but I’ll try to get my cool liver picture up soon!)
