From the NY Times in an article, titled "Why Healthy Eaters Fall for Fries," the paper looks at what a Duke Professor, Gavan J. Fitzsimons, has termed the “vicarious goal fulfillment” phenomenon.
Money quote from the article:
In studies, [Prof. Fitzsimons] has presented participants with a range of menu choices — sometimes just unhealthy items, sometimes neutral items (like a fish sandwich) and sometimes healthy choices like salad. It turned out that including a healthy option did change people’s behavior — by making them eat more unhealthily.
“When you put a healthy option up there on an otherwise unhealthy menu, not only do we not pick it, but its presence on the menu leads us to swing over and pick something that’s worse for us than we normally would,” Mr. Fitzsimons said.
Full article here: http://www.nytimes.com/2013/06/30/sun...