(P23-044-23) Recipe for Heart Health: a Randomized Crossover Trial Evaluating the Effects of Extra Virgin Olive Oil Within a Vegan Diet on Cardiometabolic Risk Factors

Objectives: High quality vegan diets are recommended for atherosclerotic cardiovascular disease (ASCVD) risk reduction, but optimal quantity of dietary fat, especially extra virgin olive oil (EVOO), within this diet is unclear.

Objective: To compare effects of high (4 tablespoon/day) vs low ( < 1 teaspoon/day) EVOO consumption within a whole-food plant-based (WFPB) vegan diet on cardiometabolic markers.

Methods: In a culinary medicine randomized crossover trial, adults with ≥5% 10-year ASCVD risk followed a high to low (H2L) or low to high (L2H) EVOO WFPB diet for 4 weeks each, separated by a 1-week washout. The primary outcome was low-density lipoprotein cholesterol (LDL-C). Linear mixed models assessed changes from baseline between each phase, including age, sex, and body weight change as covariates.

Results: Of 40 participants (75% female, BMI 32±7 kg/m², age 64±9 years mean±SD), fat intake comprised 48% and 32% of total energy in the high and low EVOO phases, respectively. Both diets resulted in significant reductions in total cholesterol, apolipoprotein B, HDL-C, glucose, hs-CRP, and LDL-C that was comparable between diets (all P>0.045), with significant diet-sequence interactions for LDL-C (P=0.003). Differences in LDL-C between diets were detected in the context of diet order (H2L: Δ-12.7 mg/dl, P=0.04 vs L2H: Δ+15.8 mg/dl, P=0.02). Similarly, the L2H order led to increased glucose, total cholesterol, and HDL-C (all P < 0.05). Over the first period, greater LDL-C reductions were observed after low EVOO (-25.5±5.1 mg/dl mean±SEM) vs high EVOO (-16.7±4.2 mg/dl), p=0.162, which were diminished over the second 4 weeks (-4.0±4.3 mg/dl vs -9.7±5.1 mg/dl, p=0.382).

Conclusions: Lipid-lowering effects resulted from both high and low EVOO WFPB diets, with more pronounced decreases after the low EVOO diet, potentially indicating that low amounts of EVOO may be more optimal for lowering CVD risk than high EVOO. Addition of EVOO after following a low EVOO pattern may impede further LDL reductions. While the low EVOO diet had greater decreases in LDL-C vs high intake, both patterns, which contained ≥30% distribution of energy from dietary fat, improved cardiometabolic risk profiles compared to baseline diets.

Funding Sources: University of Florida FSHN Department, Purjes Foundation, and Dr. Monica Aggarwal Preventive Foundation