ABSTRACT: Breakfast is considered to be one of the most important meals of the day. Its omission has been reported to be associated with increased disease risk, such as obesity, diabetes, and coronary heart disease, as well as unhealthy lifestyle and lower dietary quality. Using data from the National Adult Nutrition Survey (NANS)-a food consumption survey conducted among 1500 Irish men and women over 18 years of age, residing in the Republic of Ireland at the time the survey was conducted-we aimed to characterize breakfast regularity, identify dietary patterns associated with regular breakfast consumption, and assess the nutritional quality of such dietary patterns, using the nutrient-rich food index score NRF9.3. We determined two breakfast regularity categories and assessed dietary quality, by means of adherence to the principal component analysis derived dietary patterns and the NRF9.3 dietary index. Regular breakfast consumers were identified as those who consumed breakfast 3?4 times out of the 4 days of the collection period; such consumers comprised the majority of the population (94.4%). They had the highest adherence to healthier dietary patterns, namely, the "vegetarian" (odds ratio (OR): 2.59: 95% Confidence Interval (CI): 1.40, 4.77), "fish and vegetables" (OR: 2.88: 95% CI: 1.63, 5.10), and "breakfast cereals" (OR: 4.62: 95% CI: 2.43, 8.79) dietary patterns. Breakfast significantly contributed to the daily micronutrient intake by providing, on average, 24% of dietary fiber, 32% of iron, 30% of calcium, 32% of folate, and 37% of riboflavin. The importance of regular breakfast consumption on those who skip breakfast should be highlighted, in order to improve compliance with nutritional recommendations and adherence to a healthy lifestyle.