We tested the hypothesis that an intervention with a Mediterranean diet (MeDiet) could mitigate the well-known harmful effects of abdominal obesity on cardiovascular health.We assessed the relationship between baseline waist-to-height ratio (WHtR) and major cardiovascular events during a median follow-up of 4.8 years in the Prevention with Mediterranean Diet (PREDIMED) randomized primary prevention trial, which tested a MeDiet against a control diet (advice on a low-fat diet). We also examined whether the MeDiet intervention was able to counteract the detrimental cardiovascular effects of an increased WHtR. The trial included 7447 participants (55-80 years old, 57% women) at high cardiovascular risk but free of cardiovascular disease (CVD) at enrollment. An increased risk of CVD events (myocardial infarction, stroke, or cardiovascular death) was apparent for the highest versus the lowest quartile of WHtR (multivariable-adjusted hazard ratio: 1.98) (95% confidence interval: 1.10-3.57; linear trend: p = 0.019) only in the control-diet group, but not in the two groups allocated to intervention with MeDiet (p for interaction = 0.034). This apparent interaction suggesting that the intervention counterbalanced the detrimental cardiovascular effects of adiposity was also significant for body mass index (BMI) (p = 0.01) and waist circumference (p = 0.043).The MeDiet may counteract the harmful effects of increased adiposity on the risk of CVD.