Cane sugar does not produce the harmful carbonyl compounds; antioxidant from green tea (EGCG) reduces levels of reactive carbonyls
by Craig Weatherby
Many public health advocates and researchers believe that high-fructose corn syrup (HFCS)—a synthetically produced sweetener—promotes diabetes and obesity, because of differences in the way it is metabolized compared with the sucrose in cane sugar.
HFCS has become the sweetener of choice for many food manufacturers because, compared with cane sugar, it is cheaper, sweeter, and easier to blend into beverages.
Green tea antioxidant
lowers sodas' carbonyl levels
Dr. Ho and his team found that adding epigallocatechin gallate (EGCG)—a key antioxidant compound in tea—to drinks containing HFCS lowered the levels of reactive carbonyls, in a dose-dependent manner. In some cases, the levels of reactive carbonyls were cut in half.
Non-carbonated tea beverages containing HFCS, which already contain EGCG, had only about one-sixth the levels of carbonyls found in regular soda.
We last reported on HFCS in March, when Spanish researchers found that liquid fructose affects a genetic switch called PPAR-alpha in ways that impair the ability of rodents’ livers to break down the sweetener (See “High-Fructose Corn Syrup Takes another Hit”).
As the Spaniards reported, “Because PPAR-alpha activity is lower in human than in rodent livers, fructose ingestion in humans should cause even worse effects, which would partly explain the link between increased consumption of fructose and widening epidemics of obesity and metabolic syndrome” (Roglans N et al 2007).
Pro-aging compound abounds in corn syrup-sweetened sodas
Researchers at Rutgers University add fuel to the fire with a report that carbonated soft drinks sweetened with high-fructose corn syrup (HFCS) contain very high levels of a chemical that may contribute to the development of diabetes, particularly in children.
The scientists found that carbonated drinks containing HFCS had uniquely high levels of reactive “carbonyl” compounds.
Beverages sweetened with cane sugar (sucrose) are free of reactive carbonyls, because its fructose and glucose components are “bound” into chemically stable sucrose molecules.
And carbonation seems to fuel formation of reactive carbonyls in beverages containing HFCS. The Rutgers group found only one-third the amount of reactive carbonyl species in non-carbonated drinks containing comparable concentrations of HFCS.
These pro-aging chemicals occur at very high levels in the blood of diabetics, and are linked to complications of the disease.
Rutgers researcher Chi-Tang Ho, Ph.D. tested 11 popular sodas containing HFCS, and found “astonishingly high” levels of reactive carbonyls: a single can contained about five times more carbonyls than the blood of an adult with diabetes.
Highly reactive carbonyl compounds are associated with the “unbound” fructose and glucose molecules in HFCS, and bear a relationship to the advanced glycation end products (AGEs) found in many breads, baked goods, and browned meats.
This is how the author of a recent scientific review expressed the state of the evidence:
“Considerable evidence is now accumulating that… reactive carbonyl products are… involved in the progression of diseases, including neurodegenerative disorders, diabetes, atherosclerosis, diabetic complications, reperfusion after ischemic injury, hypertension, and inflammation” (Ellis EM 2007).
AGES and carbonyls both induce “glycation” reactions, which form compounds containing chemical bonds that generate cell-damaging free radicals.
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