The "Zero Trans-Fat" scam: Will someone please teach the FDA to use fractions?

My housemate's "Olivo Spread", which claims to be a healthy butter substitute, claims to have "zero trans fat". But the labeling lists trans-fat (more properly known as "hydrogenated" or "partially-hydrogenated oils") in the ingredients! The same goes for Ritz crackers.

What gives?

I found the answer in the article:

"Waging war on `metabolic poison',"
by Lisa Ryckman, "The Journal Gazette", April 9 2006.

The key points are:

1. Prof. Walter-Willett and his colleagues from the Harvard nutrition department estimate that
   trans-fat is killing 100,000 Americans per year! Obviously, it should be completely eliminated from our diets.
   
   
2. Fortunately, new FDA regulations require food labels to list trans-fat content, but unfortunately
   
   
3. The trans-fat content is rounded to the nearest gram, no matter how small the serving size is! Hence for items with very small serving sizes (such as butter substitutes or crackers) the "zero trans fat" may actually be a significant proportion of the product!
   
   
4. A product contains no trans fat only if the list of ingredients does not contain "hydrogenated oils" or "partially-hydrogenated" oils.

In the case of Olivo or Ritz crackers (serving sizes 14 and 15 grams, respectively), it would be consistent with the labeling to have a trans-fat content of about 1/30 by mass.

For more information, see Willett's book or bantransfats.com.