High-fructose corn syrup linked to weight gain
A research team from Princeton University has found that rats who consume high-fructose corn syrup (HCFS), the US’s most common sweetener, gain significantly more weight than rats who consume normal table sugar, despite consuming the same number of calories.
“Some people have claimed that high-fructose corn syrup is no different than other sweeteners when it comes to weight gain and obesity, but our results make it clear that this just isn’t true, at least under the conditions of our tests,” said psychology professor Bart Hoebel, who specializes in the neuroscience of appetite, weight and sugar addiction.
“When rats are drinking high-fructose corn syrup at levels well below those in soda pop, they’re becoming obese – every single one, across the board. Even when rats are fed a high-fat diet, you don’t see this; they don’t all gain extra weight.”
The study could shed light on America’s recent obesity epidemic, with vast amounts of HCFS used in the US food industry – 55% of all sweeteners. The introduction of HCFS in 1970 coincided with the beginning of the upward weight trend; today, around a third of American adults are defined as obese by the Centre for Disease Control. However, HCFS cannot be entirely to blame, with other countries, Australia included, following the obesity trend without the HCFS consumption.
The study examined weight gain, body fat and triglycerides in rats, whose water was sweetened to soft-drink levels with sugar, or half-soft-drink levels with HCFS, over six months. The rats showed signs of a condition called metabolic syndrome, including weight gain and fat deposits around the belly. Male rats were particularly affected, gaining 48% more weight than those eating a normal diet. In human terms, this would be equivalent to an 80kg man gaining 38kg.
The American Corn Refiners Association hit back at the Princeton results. “Consumers should not be misled by exaggerated studies that feed astronomical amounts of one ingredient to the study subjects, in this case rats. The medical community has long dismissed results from rat dietary studies as being inapplicable to human beings,” stated Audrae Erickson, president, Corn Refiners Association.
HCFS is rarely used in Australia, with cane sugar being cheaper and more readily available. Corn is the US’s largest crop, accounting for a quarter of harvested grains, and HCFS generates around $4.5 billion in annual profits.
What about the soy products in just about everything these days???
Sucrose is made from glucose and fructose units:
Sucrose or table sugar is obtained from sugar cane or sugar beets.
The glucose and fructose units are joined by an acetal oxygen bridge in the alpha orientation. The structure is easy to recognize because it contains the six member ring of glucose and the five member ring of fructose.
To recognize glucose look for the horizontal projection of the -OH on carbon # 4. See details on the galactose page towards the bottom.
The alpha acetal is is really part of a double acetal, since the two monosaccharides are joined at the hemiacetal of glucose and the hemiketal of the fructose. There are no hemiacetals remaining in the sucrose and therefore sucrose is a non-reducing sugar.
Sugar Processing:
Sugar or more specifically sucrose is a carbohydrate that occurs naturally in every fruit and vegetable. It is the major product of photosynthesis, the process by which plants transform the sun’s energy into food. Sugar occurs in greatest quantities in sugar cane and sugar beets from which it is separated for commercial use.
In the first stage of processing the natural sugar stored in the cane stalk or beet root is separated from the rest of the plant material by physical methods. For sugar cane, this is accomplished by:
a) pressing the cane to extract the juice containing the sugar
b) boiling the juice until it begins to thicken and sugar begins to crystallize
c) spinning the sugar crystals in a centrifuge to remove the syrup, producing raw sugar; the raw sugar still contains many impurities
d) shipping the raw sugar to a refinery where it is washed and filtered to remove remaining non-sugar ingredients and color
e) crystallizing, drying and packaging the refined sugar.
Beet sugar processing is similar, but it is done in one continuous process without the raw sugar stage. The sugar beets are washed, sliced and soaked in hot water to separate the sugar-containing juice from the beet fiber. The sugar-laden juice is purified, filtered, concentrated and dried in a series of steps similar to cane sugar processing.
Adapted from: Sugar Facts