Purpose: This study assessed the validity of the Dietary Quality Score (DQS) and investigated the association between the DQS and risk factors for cardiometabolic diseases. 

Methods: The DQS was calculated based on an updated 23-item FFQ and validated against a 376-item FFQ. A sub-sample of 450 men and women aged 18–73 years, from the Danish Diet, Cancer and Health—Next generations (DCH-NG) cohort, completed the updated 23-item FFQ. We investigated the associations between the DQS and risk factors for cardiometabolic diseases (lipids, haemoglobin A1c (HbA1c), high-sensitive C-reactive protein (hs-CRP), blood pressure (BP), waist circumference (WC), visceral and total fat mass) using linear regression models. 

Results: A high DQS, i.e. healthy dietary habits, was significantly associated with a higher intake of fruits, vegetables, fish, fibre, several vitamins and minerals and a lower intake of saturated fat. Moreover, a high DQS was significantly associated with lower levels of LDL cholesterol (P = 0.0133), Hs-CRP (P = 0.0449), WC (P = 0.0161), visceral fat (P = 0.0003), total fat mass (P = 0.0106) and total fat percentage (P = 0.0030) and significantly associated with a higher HDL cholesterol (P = 0.0379) level, when adjusting for education, smoking habits and physical activity. There was no association with total cholesterol, triglycerides, HbA1c, BP and BMI. 

Conclusion: The DQS, based on the updated 23-item FFQ, is a valid tool to classify individuals into groups with low, average and high dietary quality in the Danish population. Furthermore, a high DQS is significantly associated with lower levels of several risk factors for cardiometabolic diseases.