Cardiometabolic risk factors and type 2 diabetes are the largest contributors to the global disease burden and disease-related mortality. Visceral obesity drives the progression of multiple cardiometabolic risk factors and type 2 diabetes, and behavioral lifestyle weight loss interventions are important strategies for the prevention of these metabolic alterations. Despite the consistent evidence that the greater the body weight loss, the greater the preventive effect on cardiometabolic risk factors or diabetes, too radical strategies might be unfeasible on a large scale, and the long-term maintenance of weight reduction following restricted calorie diets represents a major challenge. Changes in diet composition acting on nutrient quality independently of changes in energy intake may be effective in cardiometabolic and diabetes risk prevention, offering a more feasible and safe alternative treatment to energy restriction. The aim of the present Special Issue is to summarize recent evidence on "Diet Quality and Risk of Cardiometabolic and Diabetes". More specifically, the impact of diet quality in terms of micro- or macronutrient composition, beyond the effect of diet restriction, on the prevention of cardiometabolic and diabetes risk as well as diabetes management, will be discussed. Personalized quality dietary interventions for cardiometabolic health and diabetes prevention, as well as possible underlying mechanisms, will also be addressed in this Special Issue.