Whole grain cereals use the entire grain seed of wheat, rye, rice, barley, corn, or oats without milling out the bran and germ. “Whole grain” means it’s the complete grain, including the bran, the germ and the endosperm. The health benefits of whole grain come from those three components working together in their natural proportions.
The 2010 Dietary Guidelines for Americans recommend that at least half of your grains are whole. For most people, that translates into at least 48 grams daily. Every General Mills Big G cereal contains at least 8 grams of whole grain per serving, and more than 20 General Mills cereals deliver 16 grams or more.
When grains are milled, or refined, the bran and germ are removed, leaving only the endosperm.
The Anatomy of Whole Grain