Menu Nutritional Labeling Had No Effect On Franchise Fast Food Sales.

From "Mandatory menu labeling didn’t change behavior at 1 fast food chain" on ScienceBlog:

in the 13 months after the [menu nutritional labeling] legislation went into effect, food-purchasing behavior at the Taco Time locations in King County [WA] was identical to that in Taco Time locations where menu boards remained unchanged.

The total number of sales and average calories per transaction were unaffected by the menu labeling.

Read the complete article here.

The nice thing about the mentioned study is that it compared restaurants in the same franchise with and without nutritional labeling over the same time period. This eliminated any food purchasing effects due to change in sales or food buying patterns at the whole franchise.