Tue Jan 1, 2013, 06:16 PM
Richard D (6,848 posts)
How Corn Syrup Might Be Making Us Hungry–and Fat
Grocery store aisles are awash in foods and beverages that contain high-fructose corn syrup. It is common in sodas and crops up in everything from ketchup to snack bars. This cheap sweetener has been an increasingly popular additive in recent decades and has often been fingered as a driver of the obesity epidemic.
These fears may be well founded. Fructose, a new study finds, has a marked affect on the brain region that regulates appetite, suggesting that corn syrup and other forms of fructose might encourage over-eating to a greater degree than glucose. Table sugar has both fructose and glucose, but high-fructose corn syrup, as the name suggests, contains a higher proportion of fructose.
To test how fructose affects the brain, researchers studied 20 healthy adult volunteers. While the test subjects consumed sweetened beverages, the researchers used fMRIs (functional magnetic resonance imaging) to measure the response of the hypothalamus, which helps regulate many hunger-related signals, as well as reward and motivation processing.
2 replies, 1133 views
How Corn Syrup Might Be Making Us Hungry–and Fat (Original post)
|Richard D||Jan 2013||OP|
Response to Richard D (Original post)
Wed Jan 2, 2013, 11:04 AM
OKIsItJustMe (15,757 posts)
1. Imaging Study Examines Effect of Fructose on Brain Regions That Regulate Appetite
Imaging Study Examines Effect of Fructose on Brain Regions That Regulate Appetite
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CHICAGO – In a study examining possible factors regarding the associations between fructose consumption and weight gain, brain magnetic resonance imaging of study participants indicated that ingestion of glucose but not fructose reduced cerebral blood flow and activity in brain regions that regulate appetite, and ingestion of glucose but not fructose produced increased ratings of satiety and fullness, according to a preliminary study published in the January 2 issue of JAMA.
Kathleen A. Page, M.D., of Yale University School of Medicine, New Haven, Conn., and colleagues conducted a study to examine neurophysiological factors that might underlie associations between fructose consumption and weight gain. The study included 20 healthy adult volunteers who underwent two magnetic resonance imaging sessions in conjunction with fructose or glucose drink ingestion. The primary outcome measure for the study was the relative changes in hypothalamic (a region of the brain) regional cerebral blood flow (CBF) after glucose or fructose ingestion.
The researchers found that there was a significantly greater reduction in hypothalamic CBF after glucose vs. fructose ingestion. “Glucose but not fructose ingestion reduced the activation of the hypothalamus, insula, and striatum—brain regions that regulate appetite, motivation, and reward processing; glucose ingestion also increased functional connections between the hypothalamic-striatal network and increased satiety.”
“The disparate responses to fructose were associated with reduced systemic levels of the satiety-signaling hormone insulin and were not likely attributable to an inability of fructose to cross the blood-brain barrier into the hypothalamus or to a lack of hypothalamic expression of genes necessary for fructose metabolism.”
Response to Richard D (Original post)
Thu Jan 3, 2013, 09:49 PM
altheablair2012 (3 posts)
2. Hi there!
A common counterargument is that it is the excess calories that are important, not the food. Simply put: just eat less, Purnell and Fair noted. “The reality, however, is that hunger and fullness are major determinants of how much humans eat, just as thirst determines how much humans drink. These sensations cannot simply be willed away or ignored.” In order to eat less (and consume fewer calories overall), they argued, then, one should avoid foods or ingredients that fail to satisfy hunger. And that, according to the results from the new study, would mean those fructose-sweetened foods—and drinks.