Fructose, the ubiquitous simple sugar used to sweeten everything from sodas to bread to chicken nuggets may lead to obesity, according to a new study from scientists at Yale University.
The study, which was published Tuesday in the Journal of the American Medical Association, showed that fructose didn't reduce blood flow in areas of the brain that control appetite -- that is, subjects who ingested fructose were told by their brains that they were still hungry, as opposed to subjects who ingested glucose, another simple sugar that is less sweet than fructose but that the brain depends on for fuel.
"It's probably not in your best interest to have high fructose-containing drinks because they're not going to cause you to be full, and you'll tend to consume more calories," said Robert Sherwin, a professor of medicine at Yale University School of Medicine.
"If you don't turn off the areas of the brain that are driving you to eat, you have a tendency to eat more than you would," Sherwin said.
The study -- which used magnetic resonance imaging of the brain -- also found that subjects' personal experience of their own hunger matched what showed up on the brain scans.
"It implies that fructose, at least with regards to promoting food intake and weight gain, is a bad actor compared to glucose," said Jonathan Purnell, an endocrinologist at Oregon Health & Science University.
Glucose is found naturally in fruits and vegetables, and the human body breaks down starches into glucose as well.
Fructose, on the other hand, is derived from sugar cane, beets and corn, and is mainly found in food additives common in processed foods. Fructose is sweeter and cheaper to produce than glucose, and it has a longer shelf life and can withstand freezing, so it has become a mainstay of the food industry.
In addition, an excess of corn in the American market led to the development of high-fructose corn syrup, a concentrated and inexpensive sweetener produced by adding fructose to corn syrup.
It sweetens nearly all processed foods and sugary drinks.
The study's results are relevant at a time when two-thirds of American adults are obese, as well as one-third of American children.
Against lobbying from the food industry, efforts have been sparked across the country to limit the amount of sugar in foods, particularly in school lunches or foods marketed to children.
But the best advice may be simple moderation.
More by I-Hsien Sherwood