[Epidemiological characteristics of preserved vegetable intake in adults in 10 areas of China].

Objective: To describe the epidemiological characteristics of intakes of different types of preserved vegetables in participants from the China Kadoorie Biobank (CKB). Methods: The CKB project conducted baseline survey, the first resurvey, and the second resurvey during 2004-2008, 2008, and 2013-2014, respectively. According to the average intake levels of salted and sour pickled vegetables in the second resurvey, the 10 survey areas were classified as the area where people mainly consumed salted vegetables, the area where people mainly consumed sour pickled vegetables, and the area where people rarely consumed preserved vegetables. For the first two areas, logistic regression model was used to describe the temporal trends and population distribution of preserved vegetable intake and analyze the distribution of other dietary factors. Results: The area where people mainly consumed salted vegetables included Qingdao, Harbin, Suzhou, and Zhejiang (baseline participant number: 204 036), while the area where people mainly consumed sour pickled vegetables included Gansu and Sichuan (baseline participant number: 105 573). In the area where people mainly consumed salted vegetables, the average intake frequencies of preserved vegetables was 3.1, 3.3, and 1.8 days/week in the baseline survey, the first resurvey, and the second resurvey, respectively, showing a declining trend (P<0.001). Similarly, the average intake frequencies of preserved vegetables were 2.8, 2.7, and 1.6 days/week in the baseline survey, the first resurvey and the second resurvey in the area where people mainly consumed sour pickled vegetables (P<0.001). At baseline survey, the married and those had lower education level tended to have more preserved vegetable intakes in both areas (P<0.001). In the area where people mainly consumed salted vegetables, the elderly had higher frequency of preserved vegetable intake (P<0.001), which was converse in the area where people mainly consumed sour pickled vegetables. In the participants with higher frequency of preserved vegetable intake, more people consumed spicy food daily and preferred salty food (P<0.05). Conclusions: The area and population specific differences in the type and frequency of preserved vegetable intake were observed in adults in the CKB project in China. Besides, the average level of preserved vegetable intake showed a declining trend. Preserved vegetable intake might be associated with other dietary habits.