Although a high-carbohydrate diet has been frequently questioned as a major contributing factor to poor diabetes control and weight gain, little has changed over the past three decades. Recently, the importance of specific foods and overall dietary patterns, rather than specific macronutrient manipulations, in diabetes care has emerged. These concepts are scientifically substantiated, and in general, healthcare professionals have been well informed. However, there are significant practice gaps that compromise the implementation of nutritional care as a critical component of lifestyle medicine for patients with diabetes. In this chapter, the core evidence-based principles of dietary management in diabetes will be discussed, followed by a discussion of these practice gaps with proposals on how best to close them.