Red Light,Green Light: The UK's new warning system:

The UK's Food Standards Agency is currently reviewing five food labeling proposals with the goal of picking a system that will help people make better-informed and healthier food choices.  The two currently favored proposals are a "simple traffic light" system (with red, amber, and green circles, which supposedly respectively indicate: eat sparingly, eat in moderation, and eat plenty) and a "multiple traffic light system" (indicating low, medium, or high for levels of fat, salt, sugar, and saturates).  Other proposals include an "extended traffic light" system containing a range of five colors as opposed to three (I am trying to imagine the confusion that would ensue if such a system replaced all current traffic lights) and a logo to be placed on specific foods deemed to be "healthy."

What kind of color would this get?