Associations of dietary patterns with metabolic syndrome and insulin resistance: a cross-sectional study in a Japanese population.

The associations of dietary patterns with metabolic syndrome (MetS) and insulin resistance have not been fully investigated in the Japanese population. A cross-sectional study was performed on 513 subjects without treatment for diabetes who had participated in the baseline survey of a cohort study in Tokushima Prefecture, Japan. Frequencies of consumption of 46 foods and beverages were assessed using a questionnaire. MetS was diagnosed using the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III) criteria. Logistic and linear regression analyses were used to examine the associations of the dietary patterns with the prevalence of MetS, its components, and the Homeostasis Model of Assessment-Insulin Resistance (HOMA-IR). Using principal component analysis, four dietary patterns were extracted: prudent diet (high intake of vegetables and fruits); high fat/Western (high intake of fried foods, fried dishes and meat); bread and dairy products; and seafood patterns. After adjustment for sex, age, and other potential confounders, prudent diet pattern scores were inversely correlated with the prevalence of reduced serum high-density lipoprotein cholesterol (P=0.04) and high blood pressure (P=0.05), and bread and dairy products pattern scores were correlated with a lower prevalence of abdominal obesity (P=0.04) and high plasma glucose (P=0.04). The high fat/Western pattern was positively correlated with HOMA-IR (P=0.04). Prudent dietary pattern and bread and dairy products pattern may be correlated with a lower prevalence of some components of MetS. A high fat/Western dietary pattern may be positively associated with insulin resistance in the Japanese population.