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LC FP
Fri, Jul-06-07, 15:59
http://www.medscape.com/viewarticle/559344?src=mp


Relative to baseline, 24-hour postprandial triglyceride profiles were increased by 212% ± 59% in the fructose-consuming group (P < .0001). In contrast, levels declined by about one third (−30% ± 23%) in the glucose-consuming group. In addition, fasting plasma levels of low-density lipoprotein cholesterol (LDL-C); apolipoprotein B; and small, dense LDL-C, as well as postprandial levels of remnant lipoprotein (RLP)-triglycerides and RLP-cholesterol, were all significantly increased (P < .01) in the fructose group. By comparison, these levels remained unchanged in the glucose group.

Fructose-consuming participants also demonstrated increased plasma concentrations of the atherogenic risk factors oxidized LDL-C (P < .0001) and intracellular adhesion molecule (P < .05), but those consuming glucose did not.

"Consumption of sugar-sweetened beverages containing fructose has increased by 135% from 1977 to 2001 and may be a contributing factor to an increased incidence of metabolic syndrome," the authors note in their abstract.

According to Dr. Havel, most soft drinks in the United States are sweetened with high-fructose corn syrup, which is a mixture of about 55% fructose and 45% glucose.

"It is known that fructose, after being metabolized by the liver, is more likely to go into a lipogenic pathway than glucose," Dr. Havel noted. "So these results were not surprising to us, but the magnitude of some of the changes was striking," he added.

"While this is an interim report, the findings do suggest that persons at risk for cardiovascular disease, diabetes, or hyperlipidemia should limit consumption of fructose-sweetened beverages. It is unclear, however, whether a nonatherogenic level of fructose consumption exists, and what that might be."

Dodger
Fri, Jul-06-07, 16:24
I'm not a fan of HFCS, but regular sugar is 50% fructose and 50% glucose. Not a whole lot different than HFCS.

Nancy LC
Fri, Jul-06-07, 16:28
There's more than one sort of HFCS, one has 80 or more percent of fructose.

LC FP
Fri, Jul-06-07, 16:31
regular sugar is 50% fructose and 50% glucose. Not a whole lot different than HFCS
Mike do you know if HFCS is a mixture of hydrolyzed monosaccharides? Maybe the disaccharide nature of sucrose exerts some control over fructose absorption and disposal.

Nancy LC
Fri, Jul-06-07, 16:39
High-fructose corn syrup is produced by milling corn to produce corn starch then processing that corn starch to yield corn syrup that is almost entirely glucose, and then adding enzymes that change the glucose into fructose. The resulting syrup (after enzyme conversion) contains approximately 90% fructose and is HFCS 90. To make the other common forms of HFCS (HFCS 55 and HFCS 42) the HFCS 90 is mixed with 100% glucose corn syrup in the appropriate ratios to form the desired HFCS syrup. The enzyme process that changes the 100% glucose corn syrup into HFCS 90 is as follows:

1. Cornstarch is treated with alpha-amylase to produce shorter chains of sugars called oligosaccharides.
2. Glucoamylase breaks the sugar chains down even further to yield the simple sugar glucose.
3. Glucose isomerase converts glucose to a mixture of about 42% fructose and 50–52% glucose with some other sugars mixed in.

While inexpensive alpha-amylase and glucoamylase are added directly to the slurry and used only once, the more costly glucose-isomerase is packed into columns and the sugar mixture is then passed over it, allowing it to be used repeatedly until it loses its activity. This 42–43% fructose glucose mixture is then subjected to a liquid chromatography step where the fructose is enriched to approximately 90%. The 90% fructose is then back-blended with 42% fructose to achieve a 55% fructose final product. Most manufacturers use carbon absorption for impurity removal. Numerous filtration, ion-exchange and evaporation steps are also part of the overall process

The wikipedia article is very interesting.
http://en.wikipedia.org/wiki/High_fructose_corn_syrup

Dodger
Fri, Jul-06-07, 16:44
Mike do you know if HFCS is a mixture of hydrolyzed monosaccharides? Maybe the disaccharide nature of sucrose exerts some control over fructose absorption and disposal.That may well be it. The article Nancy posted makes it sound like the HFCS is just a mixture of monosaccharides.

LC FP
Fri, Jul-06-07, 16:58
Thanks Nancy. Sounds like a pretty complicated process. And yet HFCS is dirt cheap and sugar is expensive. I guess import tariffs on sugar have something to do with that. And that is the fault of the politicians.