Relationship between dietary factors and the number of altered metabolic syndrome components in Chinese adults: a cross-sectional study using data from the China Health and Nutrition Survey

Objectives To study the correlation between dietary factors and the number of altered metabolic syndrome components (MetS) in Chinese adults systematically. Setting A cross-sectional study using demographic and dietary data of adults aged 18-75 years from the China Health and Nutrition Survey (2009) was conducted in nine provinces in China. Participants There were 6034 eligible subjects (2800 men and 3234 women) in this study. Outcomes The primary outcome of this study were diet assessments and the number of altered MetS components. Dietary intake was measured using a combination of a 3-day period with 24-hour and household food inventory; average daily intakes of nutrients were estimated according to the Chinese Food Composition Table. Blood samples were analysed in a national central laboratory and the number of clustering MetS components was calculated by adding the presence of each MetS component. Results After adjusting for covariates, and taking zero MetS as comparison, the high risk factors correlating with increased numbers of altered MetS components in men were higher intake of protein (70.4-73.4 g; Ptrend=0.0004), cholesterol (238.7-266.6 mg; Ptrend=0.004), meat (90.6-105.7 g; Ptrend=0.016), fish/seafood (30.4-42.3 g; Ptrend=0.001), and lower intake of coarse cereals (16.5-12.7 g; Ptrend=0.051), tubers (37.3-32.7 g; Ptrend=0.030), and dietary fibre (11.7-11.5 g; ANCOVA p=0.058). Meanwhile, the high risk factors correlating with the increased number of altered MetS components in women were higher intake of wheat (101.9-112.6 g; Ptrend=0.066) and sodium (3862.3-4005.7 mg, Ptrend=0.032), and lower intake of beta-carotene (1578.6-1382.7 mu g; Ptrend=0.007), milk, and dairy products (17.8-11.5 g; Ptrend=0.002). Conclusions Some foods and nutritional factors correlate with an increased number of altered MetS components in Chinese adults. More prospective, multicentre and clinical research work to further examine these associations is underway.