By Angela Pirisi, published on January 1, 2003 - last reviewed on December 8, 2008
Sugar addiction is more than a trite expression people use to
describe their sweet tooth. A pattern of fasting and overloading on
sugary foods may foster dependence, according to a study published in
"People with a genetic predisposition for addiction can become
overly dependent on sugar, particularly if they periodically stop eating
and then binge," warns Bart Hoebel, Ph.D., a psychologist at Princeton
University who led the study. "Laboratory experiments with rats showed
that signs of sugar dependence developed over the course of 10 days. This
suggests that it does not take long before the starve-binge behavior
catches up with animals, making them dependent."
Earlier research found that this pattern sensitizes both dopamine
and opioid receptors in rats. A cycle of deprivation and excessive sugar
intake reinforces bingeing.
Abstinence also triggers withdrawal symptoms that resemble those of
drug addiction, such as anxiety, chattering teeth and tremors. The taste
of sugar makes the brain release natural opioids, and the bingeing causes
"There is something about this combination of heightened opioid and
dopamine responses in the brain that leads to dependency," explains
Hoebel. "Without these neurotransmitters, the animal begins to feel
anxious and wants to eat sweet food again."
The rats exhibited behavioral changes even when sugar was replaced
with the artificial sweetener saccharin. "It appears to be the sweetness,
more than the calories, that fuels sugar dependence," says Hoebel.
Although researchers still don't understand how people can curb
their sugar cravings, they do know that withdrawal symptoms and dips in
dopamine levels aren't evident when meals are moderate and regularly