To investigate the association of major dietary patterns with the risk of impaired glucose and insulin homeostasis during a 3-year follow-up.

Fasting serum insulin (FSI), fasting (FSG) and 2 h serum glucose (2h-SG) were measured at baseline and again after 3 years. Dietary intakes were evaluated using a validated 168-item semi-quantitative FFQ and major dietary patterns were obtained using principal component analysis. Logistic regression models were used to estimate the occurrence of impaired fasting glucose (IFG), impaired glucose tolerance (IGT), pre-diabetes (IGT/IFG), β-cell dysfunction and hyperinsulinaemia across tertiles of dietary patterns, with adjustment for potential confounding variables.

Tehran Lipid and Glucose Study.

Iranian men and women (n 904).

Mean age of participants was 38·7 (sd 11·3) years and 44·6 % were men. Major dietary patterns were Western, traditional and healthy, which explained 25·2 % of total variance in food intake. There was a positive association between Western and traditional scores with 3-year change in 2h-SG, while the healthy pattern was negatively related to 3-year changes in FSG, 2h-SG, FSI and homeostasis model assessment of insulin resistance. Highest compared with the lowest tertile of the Western dietary pattern was accompanied by a higher risk for development of IGT (OR=3·09; 95 % CI 1·28, 7·50); a higher score on the healthy dietary pattern was associated with a significantly reduced risk of hyperinsulinaemia (OR=0·53; 95 % CI 0·28, 0·94).

Our findings showed that adherence to a Western dietary pattern may be a risk factor for the development of IGT, while a healthy dietary pattern may prevent hyperinsulinaemia.

To investigate biomarkers of nutrition associated with chronic disease absence for an Aboriginal cohort.

Screening for nutritional biomarkers was completed at baseline (1995). Evidence of chronic disease (diabetes, CVD, chronic kidney disease or hypertension) was sought from primary health-care clinics, hospitals and death records over 10 years of follow-up. Principal components analysis was used to group baseline nutritional biomarkers and logistic regression modelling used to investigate associations between the principal components and chronic disease absence.

Three Central Australian Aboriginal communities.

Aboriginal people (n 444, 286 of whom were without chronic disease at baseline) aged 15–82 years.

Principal components analysis grouped twelve nutritional biomarkers into four components: ‘lipids’; ‘adiposity’; ‘dietary quality’; and ‘habitus with inverse quality diet’. For the 286 individuals free of chronic disease at baseline, lower adiposity, lower lipids and better dietary quality components were each associated with the absence at follow-up of most chronic diseases examined, with the exception of chronic kidney disease. Low ‘adiposity’ component was associated with absence of diabetes, hypertension and CVD at follow-up. Low ‘lipid’ component was associated with absence of hypertension and CVD, and high ‘dietary quality’ component was associated with absence of CVD at follow-up.

Lowering or maintenance of the factors related to ‘adiposity’ and ‘lipids’ to healthy thresholds and increasing access to a healthy diet appear useful targets for chronic disease prevention for Aboriginal people in Central Australia.