Association between fatty acids and the risk of impaired glucose tolerance and type 2 diabetes mellitus in American adults: NHANES 2005−2016

BACKGROUND: Fatty acids (FAs) play a major role in regulating insulin sensitivity. However, owing to dietary quantitative tools, it has been challenging to study the dietary FAs in previous studies. There is a lack of knowledge regarding the associations between dietary FAs and the risk of impaired glucose tolerance (IGT) and type 2 diabetes mellitus (T2DM). METHODS: Dietary FAs, adjustment of variables including age, sex, race, educational level, poverty to income ratio, body mass index, smoking, hypertension, physical activity, and diabetes data were extracted from the National Health and Nutrition Examination Survey 2005–2016. A multivariate logistic regression model was used to determine the associations between FA intake and the risk of IGT and T2DM. RESULTS: This serial cross-sectional study included 9082 samples. After adjusting all the variables, a negative correlation was observed between total saturated FA and the risk of IGT (OR = 0.991, 95% (CI): 0.985–0.998, P = 0.024). Total FA at quintile 4 was negatively correlated with T2DM (OR = 0.714, 95% CI: 0.532–0.959, P = 0.025) compared with quintile 1. Factor analysis identified four factors of which F4 was negatively associated with the risk of T2DM (OR = 0.824, 95% CI: 0.715–0.949, P = 0.029). Based on this factor, we identified an unsaturated FA signature (n = 4 FAs, including octadecenoic acid (18:1), octadecadienoic acid (18:2), octadecatrienoic acid (18:3), and eicosenoic acid (20:1)). CONCLUSIONS: Several unsaturated FAs with high proportions in natural oils may reduce the risk of T2DM.