Impact of a 12-week personalized dietary intervention on vascular function and cardiovascular risk factors

Objective. Given the interaction between insulin resistance (IR) and cardiovascular risk, we examined whether a personalized diet according muscle insulin-resistant (MIR) or liver insulin-resistant (LIR) phenotypes improves vascular function and cardiovascular disease risk factors. Methods. Individuals were randomized to a personalized phenotype diet (PhenoDiet) A or B and followed a 12-week low-fat, high-protein (LFHP) diet or high-monounsaturated fatty acid (HMUFA) diet (PhenoDiet A; MIR/HMUFA-LIR/LFHP; PhenoDiet B: MIR/LFHP-LIR/HMUFA). We included 101 participants. Results. Dietary interventions decreased blood pressure, total cholesterol, HDL-cholesterol and the Framingham risk score (all P<0.05), improved IR ((Matsuda index, HOMA-IR) P<0.001), but not vascular function (P=0.485). Changes in outcome parameters were not significantly different between PhenoDiet groups. The LFHP diet resulted in more pronounced improvements in cholesterol, DBP, and IR compared to the HMUFA diet (all P<0.05). Conclusion. A 12-week healthy diet improves metabolic and cardiovascular outcomes, but not vascular function in IR adults with overweight or obesity. Whilst the LFHP diet resulted in greater improvements in cardiometabolic risk markers than the HMUFA diet, we found no significant differences between the PhenoDiet groups.