Link Between Diet Quality and Lifestyle Factors Among Young Adults in Saudi Arabia

Background/Objectives: Poor diet quality is common among young Saudi adults, characterised by high fast-food intake and low fruit and vegetable consumption. This study investigated the association between diet quality and lifestyle factors using a validated short Healthy Eating Index (sHEI). Methods: This study adopted a cross-sectional design, gathering responses through a self-completed online questionnaire. Demographic data were collected. Diet quality was assessed using the Arabic version of the sHEI, physical activity was evaluated with the Arabic short form of the International Physical Activity Questionnaire (IPAQ), and sleep quality was measured using the Athens Insomnia Scale (AIS). Saudi residents aged 18–25 years were eligible; pregnant or lactating individuals and those with chronic conditions affecting dietary intake were excluded. Results: Among 478 participants (mean age 21.1 ± 1.9 years), 88.1% were female, 24.7% were overweight or obese, and half reported poor diet quality. Moderation scores were slightly higher (54.2% high), whereas adequacy scores were nearly equal (49.8% high and 50.2% low). Most participants reported low physical-activity levels (78.5%) and poor sleep quality (55.2%). Sleep quality was significantly associated with all diet quality measures, increasing the odds of good total sHEI (OR = 1.74, p = 0.003), adequacy (OR = 1.49, p = 0.034), and moderation (OR = 1.54, p = 0.021). Conclusions: Sleep quality is significantly associated with diet quality among young Saudi adults. While body mass index and physical activity showed no significant associations, improving sleep quality may promote healthier dietary behaviours. Future studies should explore pathways linking sleep and diet.