ZONE Friendly has to do with the Insulin stimulating Carbs and hormonal control based on the types of carbs.
ZONE Friendly also has to do with the ypes of fat in the food.
ZONE Friendly also has to do with the type and quality of Protein and its associated inherent fat.
Zone Friendly has to do with all three components Protein, Fat, and carbs working together in the correct type and the correct amount to keep your blood sugar stable- hormonal control.
A label will tell you the amounts of P, F, and/or C, and the type;
BUT it will not tell you whether it is ZONE Friendly.
To get familiar with ZONE Friendly foods, use this web-site, specifically you can satrt with the FOOD BLOCK GUIDE under TOOLS on the menu.
You can also refer to the books by Dr. Barry Sears to get a better understanding.
the latest one, "Toxic Fat", is a very good book, explaining the basics, without being too technical.
IF you do not want to buy one of his books, check out your local library.
Bottom line is more than just balancing 7 grams protein, 3 grams fat, and 9 grams Carbs.
The EASIEST way is to START with the Food Block Guide and the ZONE QUick Start Guide on this website. http://www.zonediet.com/tools/quick-start-guide