BackgroundLowering insulin resistance and dyslipidaemia may not only enhance glycaemic control but also preserve the β-cell function, reducing the overall risk of developing type 2 diabetes (T2D). The current study was aimed to evaluate the effects of curcumin and/or long-chain omega-3 polyunsaturated fatty acids (LCn-3PUFA) supplementation on glycaemic control and blood lipid levels in individuals at high risk of developing T2D.MethodsThis was a 2 × 2 factorial, randomised, double-blinded, placebo-controlled study. Participants were allocated to either double placebo (PL) or curcumin plus placebo matching for LCn-3PUFA (CC), or LCn-3PUFA plus placebo matching for curcumin (FO), or curcumin plus LCn-3PUFA (CC-FO) for twelve weeks. Primary outcome of the trial was glycaemic indices (HbA1C, fasting glucose and insulin). Insulin resistance and sensitivity is measured using homeostatic model assessment model.ResultsA total of sixty-four participants (PL, n = 16; CC, n = 15; FO, n = 17, CC-FO, n = 16) were included in the final analysis. Post-intervention, HbA1c and fasting glucose remained unchanged across all the groups. Insulin sensitivity was significantly improved in the CC supplemented group (32.7 ± 10.3%) compared to PL (P = 0.009). FO and CC-FO tended to improve insulin sensitivity by 14.6 ± 8.5% and 8.8 ± 7.7% respectively, but the difference did not reach significance. Triglyceride levels were further increased in the PL (26.9 ± 7.4%), however, CC and CC-FO supplementation reduced the triglycerides, FO resulted in the greatest reduction in triglycerides (− 16.4 ± 4.5%, P < 0.001).ConclusionReduction in insulin resistance and triglycerides by curcumin and LCn-3PUFA appears to be attractive strategies for lowering the risk of developing T2D. However, this study failed to demonstrate complimentary benefits of curcumin and LCn-3PUFA on glycaemic control.Trail registrationACTRN12615000559516.Electronic supplementary materialThe online version of this article (10.1186/s12944-019-0967-x) contains supplementary material, which is available to authorized users.

Introduction: Plasma amyloid beta (Aβ)1-42/Aβ1-40 ratio, phosphorylated-tau181 (p-tau181), glial fibrillary acidic protein (GFAP), and neurofilament light (NfL) are putative blood biomarkers for Alzheimer's disease (AD). However, head-to-head Pratishtha Chatterjee and Steve Pedrini contributed equally to this work.