Have you started checking grocery shelves to see which packaged foods contain "trans fat" -- the kind reviled by some nutritionists as the worst of the bad fats?

Many packages don't yet say. But come January, manufacturers of packaged food will have to list the amount of trans fat their products contain.

In anticipation of this change in federal labeling rules, some food companies have been trying for two years to score points with consumers by highlighting snacks and baked goods that contain zero trans fat.

Find out more about the trans fat labeling policy that will become effective January 2006 at http://www.mercurynews.com/mld/mercurynews/business/12917262.htm.