Major dietary patterns and their relationship to obesity among urbanized adult Tibetan pastoralists

Background and Objectives: This study investigated major dietary patterns and their relationship to obesity among urbanized Tibetan pastoralists. Methods and Study Design: Using a cross-sectional design, this study assessed 782 urbanized Tibetan pastoralists aged 18-84 y. A food frequency questionnaire and anthropometric measurements were conducted in 2018. Principal component analysis was used to identify dietary patterns. Logistic regression was applied to compare the risks for overweight (BMI >=24 kg/m2), obesity (BMI >=28 kg/m2), and central obesity (waist circumference >=80 cm for women and >=85 cm for men) across quintiles of dietary pattern scores after controlling for gender, age, education, medical insurance, smoking status, alcohol consumption and physical activity. Results: This study identified three major dietary patterns: an urban pattern characterized by high intake of vegetables, tubers/roots, and refined carbohydrates; a western pattern characterized by sugary drinks, snacks, and desserts; and a pastoral pattern characterized by 'tsamba' (roasted Tibetan barley), Tibetan cheese, and buttered/milk tea. Subjects in the highest quintile of urban pattern scores were more likely to be overweight (OR=2.58, 95% CI 1.48-4.49) ('p'-for-trend=0.001), obese (2.94, 1.57-5.49) ('p'-for-trend=0.001), and centrally obese (1.94, 1.12-3.36) ('p'-for-trend=0.019) compared to those in the lowest quintile with confounders controlled. The western dietary pattern was positively associated with overweight ('p'-for-trend=0.037). No clear association was observed for the pastoral dietary pattern. Conclusions: Urban and western dietary patterns independently predict the likelihood of being overweight. Improved nutrition education may contribute to healthier eating behaviors, thus reducing or preventing obesity.