ABSTRACT
BACKGROUND: Individual vegetable oils have a characteristic fatty acids (FA) composition and unique phytonutrient profiles, enabling formulation of oil blends that may have health-promoting effects. OBJECTIVE: The primary objective of this study was to investigate effects of 2 oil blends made with refined rice bran, flaxseed, and sesame oils, with distinct monounsaturated to saturated FA, polyunsaturated to saturated FA, and omega-3 (n-3) to omega-6 FA ratios and different phytonutrient concentrations on blood lipid profile, compared with refined olive oil as a control. The secondary outcomes were other markers of cardiometabolic health. METHODS: A parallel-design, randomized controlled trial compared consumption of 30 g of allocated intervention oil per day for a period of 8 wk. The study recruited 143 borderline hypercholesterolemic (LDL cholesterol: 3.06-4.51 mmol/L) Chinese volunteers between 50 and 70 y old and with a BMI (kg/m2) ≤27.5. All outcomes were measured every 2 wk, and the time × treatment interactions and the main effects of treatment and time were analyzed using an intention-to-treat approach. RESULTS: Compared with baseline (week 0), there were significant reductions during the post-intervention time points in serum total cholesterol (-3.47%; P < 0.0001), LDL cholesterol (-4.16%; P < 0.0001), triglycerides (-10.3%; P < 0.0001), apoB (-3.93%; P < 0.0001), total to HDL-cholesterol (-3.44%; P < 0.0001) and apoB to apoA1 (-3.99%; P < 0.0001) ratios, systolic and diastolic blood pressures (-3.32% and -3.16%, respectively; both P < 0.0001), and serum glucose (-1.51%; P < 0.05) and a small but significant increase in body weight (+0.7%; P < 0.001) for all 3 intervention oils but no effects of intervention on HDL-cholesterol or apoA1 concentration. No significant effects of treatment or time × treatment interactions were found. CONCLUSIONS: Using blended vegetable oils that are extensively consumed in Asia, this study found that specific oil blends can improve blood lipid profile and other cardiometabolic parameters, to a similar extent as refined olive oil, in Chinese adults with borderline hypercholesterolemia. This trial is registered at www.clinicaltrials.gov as NCT03964857.
