Mediterranean diet plus physical activity reduces postprandial triglyceridemia in adults with abdominal obesity

BACKGROUND AND AIMS: No randomized clinical trial (RCT) using a factorial design has yet tested the hypothesis that a healthy diet and regular physical activity (PA) have synergistic effects on cardiometabolic risk. OBJECTIVE: to assess the synergy between a Mediterranean diet (MedDiet) and regular PA on postprandial triglyceridemia (TG) and other lipid risk factors. METHODS AND RESULTS: In this 2x2 factorial 16-week RCT, two hundred men and women with abdominal obesity and moderate hypertriglyceridemia (TG ≥ 1.5 mmol/L) were randomly assigned to one of four groups: 1-control, 2-MedDiet only, 3-PA only and 4-MedDiet + PA. MedDiet groups were counseled to adhere to a MedDiet and received key MedDiet foods. The PA intervention targeted 150 min/week of moderate intensity exercise (65 % of measured VOpeak). Controls were asked to maintain their usual dietary and PA habits. Postprandial serum TG was measured 4h after consumption of 35.1g fat/m of body surface area. The dropout rate among participants (mean [SD] age, 53.8 [10.6] years; 75.5 % women) was 2.5 %. There was a small synergistic effect of the MedDiet and PA on 4h postprandial TG (P = 0.025), the MedDiet + PA group exhibiting the lowest post-intervention 4h TG concentrations of all groups. There was also evidence of a small synergistic effect between treatments in reducing apolipoprotein B concentrations (P = 0.077) measured on the last day of intervention, which was no longer observed when measured 48 h after the end of intervention. CONCLUSION: The combination of a MedDiet and regular PA may have small, short-lived synergistic effects on postprandial TG concentrations and other cardiometabolic risk factors.