Postprandial Saturated Fatty Acids Increase the Risk of Type 2 Diabetes: A Cohort Study in a Chinese Population

Context: Experimental evidence suggests saturated fatty acids (SFAs) are associated with insulin resistance, but results from epidemiological studies on fasting SFAs-diabetes risk are inconsistent. Objective: We investigated SFA (fasting and 2-hour postprandial) profiles and diabetes risk. Design Setting: A total of 8940 participants were recruited for the Harbin People's Health Study in 2008. Serum SFAs (fasting and 2-hour postprandial) at baseline in Chinese men and women without diabetes were profiled, and type 2 diabetes was ascertained using World Health Organization criteria after 4 to 7 years of follow-up. Outcome: Associations between 2-hour postprandial SFA (2h-SFA) and diabetes. Results: At baseline, incident cases of diabetes were older with a higher body mass index and waist circumference. After a mean follow-up of 6.7 years, 658 incident cases of diabetes occurred. After propensity score computation and inverse probability of treatment weighting (IPTW) estimation, fasting SFAs were unrelated to diabetes risk but IPTW-adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the highest tertile of 2-hour postprandial stearic acid (2h-SA), 2-hour postprandial palmitic acid (2h-PA), and 2h-SFA for diabetes risk were 2.50 (2.08 to 3.16), 1.56 (1.23 to 2.02), and 1.70 (1.34 to 2.17), respectively (P-trend < 0.0001). Similarly, 2h-SA/fasting SA, 2h-PA/fasting PA, and 2h-SFA/fasting SFA ratios [IPTW-adjusted OR (95% CI): 2.94 (2.39 to 3.58), 2.31 (1.80 to 2.93), and 2.42 (1.91 to 3.11), respectively; P-trend < 0.0001] predicted the diabetes risk. Conclusions: Higher serum 2h-SFA (but not fasting SFA) independently predicted diabetes risk.