The U.S. FDA defines whole grains as consisting of the intact, ground, cracked, or flaked fruit of the grains whose principal components, the starchy endosperm, germ, and bran, are present in the same relative proportions as they exist in the intact grain. We evaluated the effect of applying the FDA definition of whole grains to the strength of scientific evidence in support of claims for risk reduction of cardiovascular disease (CVD). We concluded that using the FDA definition for whole grains as a selection criterion is limiting, because the majority of existing studies often use a broader meaning to define whole grains. When considering only whole grain studies that met the FDA definition, we found insufficient scientific evidence to support a claim that whole grain intake reduces the risk of CVD. However, a whole grain and reduced risk of CVD health claim is supported when using a broader concept of whole grain to include studies that considered intake of fiber-rich bran and germ as well as whole grain. This type of analysis is complicated by diversity in nutrients and bioactive components among different types of whole grains.