Characteristics and dietary practices among adults with experience following a ketogenic diet in Saudi Arabia: a cross-sectional study

The ketogenic diet (KD) has gained substantial popularity worldwide, particularly as a strategy for weight loss and metabolic health. Although previous studies have examined public knowledge and perceptions of the KD, little is known about the knowledge, dietary practices, and adherence of individuals who actively follow the diet. This study aimed to evaluate KD-related knowledge, dietary practices score, adherence, and factors associated with knowledge and practice among adults who had ever followed KD in Saudi Arabia. A descriptive cross-sectional study was conducted among adults aged ≥ 18 years residing in Saudi Arabia who had ever followed the KD. Participants were recruited through social media platforms using an online questionnaire. The survey collected information on sociodemographic characteristics, motivations for adopting the KD, sources of dietary information, KD-related knowledge, dietary practices score, and adherence. Knowledge and practice scores were calculated using predefined scoring systems, and multivariable regression analyses were performed to identify factors associated with higher knowledge and practice scores. A total of 227 participants completed the survey (70.9% female; mean age 36.0 ± 12.5 years). Weight management was the primary reason for adopting the KD, while social media was the most frequently reported source of information. Participants demonstrated a score of 58% about knowledge of KD principles, nutritional composition, and potential health effects, with average knowledge scores of approximately 58%. In contrast, dietary practice scores indicated generally good adherence to recommended KD behaviors, although maintaining recommended macronutrient ratios remained a common challenge. Higher knowledge scores were associated with greater physical activity and the use of vitamin B12 and magnesium supplements, whereas higher educational attainment and vitamin B-complex supplementation were independently associated with better dietary practice score. the sampled participants who ever had following KD in Saudi Arabia demonstrated limited knowledge of the diet and limited adherence to the recommended macronutrient ratio and persistent misconceptions regarding nutrient composition, electrolyte management, and long-term safety highlight the need for evidence-based nutrition education and professional guidance. Improving access to reliable nutrition information may support safer and more effective implementation of KD in community settings.