When potato-chip makers came up with the slogan "Betcha can't eat just one," it wasn't false advertising.
At least, not for people hard-wired to crave junk food.
According to a new study involving young women, just looking at a milkshake activates the same areas of the brain that light up when an addict sees cocaine, Reuters reports.
Researchers found the most brain activity among women who rated high on a scale of addictive eating behaviour.
"If certain foods are addictive, this may partially explain the difficulty people experience in achieving sustainable weight loss," writes lead author Ashley Gearhardt of Yale University in the Archives of General Psychiatry.
Previous research confirms what junk-food addicts already know: It's tough to kick a fat and sugar habit.
In a 2010 study at Scripps Research Institute in Florida, scientists found addictive behaviour in rats given an unlimited supply of high-calorie foods.
Over time, the rats showed less activity in the pleasure centres of the brain and needed to eat more to get a junk food "high." And unlike rats given a healthy diet or restricted portions of junk food, the rats offered a self-serve buffet of sweets and fatty treats started bingeing, doubling their initial weight.
Food advertisers play a big role in the obesity epidemic, according to researchers in the milkshake study, who suggest that reducing visual "cues" - such as billboards - would help food addicts avoid temptation.
In other words, out of sight, out of mind.
What do you think: Would less mouth-watering advertising for fatty, junky food help you cut back that craving?