This study investigates the associations between four healthy dietary scores and the risk of 48 individual chronic diseases using data from the UK Biobank. Higher Alternate Mediterranean Diet (AMED) scores were associated with a lower risk of 32 diseases, while Alternate Healthy Eating Index-2010 (AHEI-2010) and Healthful Plant-based Diet Index (HPDI) scores were inversely associated with 29 and 23 diseases, respectively. Anti-Empirical Dietary Inflammatory Index (AEDII) showed inverse associations with 14 diseases but positive associations with two. The findings support dietary guidelines for chronic disease prevention.