The aim of the present study was to assess if a simple dietary quality index (SDQI) is a useful indicator for nutritional quality in the Danish diet. Data from the Danish National Dietary Survey 2000–2 for adults (n 3151; age 18–75 years) were used to construct an SDQI based on the intake of dietary fibre and saturated fat. The SDQI was used to rank the individuals into three subgroups: the 25 % closest in meeting the recommended intakes of saturated fat and dietary fibre (compliers), the 25 % furthest away (non-compliers) and the 50 % in between (intermediates). Significant differences in food and nutrient intake between these subgroups were identified by intakes of food groups and intakes of nutrients followed by non-parametric tests. Compared with the Nordic Nutrition Recommendations 2004 and the Danish Dietary Guidelines 2005, compliers had a significantly better nutrient profile than intermediates and non-compliers, as the diet of compliers contained more whole-grain cereals, fruits, vegetables and fish, and more frequently low-fat dairy products, lean meats and boiled potatoes. The diet of all subgroups, especially non-compliers, had a high content of nutrient-poor, energy-dense foods, for example, salty snacks, confectionery, and beverages, for example, soft drinks and alcohol. The SDQI is a simple and useful tool to characterise the diet quality of Danish adults.