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.
“Increases in fructose consumption have paralleled the increasing prevalence of obesity, and high-fructose diets are thought to promote weight gain and insulin resistance. Fructose ingestion produces smaller increases in circulating satiety hormones compared with glucose ingestion, and central administration of fructose provokes feeding in rodents, whereas centrally administered glucose promotes satiety,” according to background information in the article. “Thus, fructose possibly increases food-seeking behavior and increases food intake.” How brain regions associated with fructose- and glucose-mediated changes in animal feeding behaviors translates to humans is not completely understood.
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.”
insanity-rehab said: That’s a step closer to going vegan. Have you thought about that?
Indeed, it is a step closer to going vegan. I honestly have entertained the thought of going vegan, and I seriously lack the education about being vegan. Once I gain adequate knowledge about being vegan, and get a hold of my renewed commitment to vegetarianism, I’ll give it a more serious consideration. That is not to say that I haven’t been enjoying vegan dishes here and there. I am surprised by how colorful they can get; it’s quite eye-opening!
Oh, so it has happened. I am attempting to become a fully-fledged vegetarian starting at the beginning of 2013 for health and well-being purposes. To combat any potential relapses, I decided to try it for a week, and will make note of any complications. Another good idea will be to take a complete physical examination, since I haven’t had one in more than a year. If all goes as planned, it will be one of the most life-altering decisions I have ever taken, not that my life compels me to make such decisions. I look forward to experiencing all sorts of alternatives that this new lifestyle will provide.
For 25 years, the rhesus monkeys were kept semi-starved, lean and hungry. The males’ weights were so low they were the equivalent of a 6-foot-tall man who tipped the scales at just 120 to 133 pounds. The hope was that if the monkeys lived longer, healthier lives by eating a lot less, then maybe people, their evolutionary cousins, would, too. Some scientists, anticipating such benefits, began severely restricting their own diets.
The results of this major, long-awaited study, which began in 1987, are finally in. But it did not bring the vindication calorie restriction enthusiasts had anticipated. It turns out the skinny monkeys did not live any longer than those kept at more normal weights. Some lab test results improved, but only in monkeys put on thewhen they were old. The causes of death — , heart disease — were the same in both the underfed and the normally fed monkeys.