The popular framing that you can outrun a bad diet is partly true: vigorous exercise does reduce cardiovascular risk even on a poor diet. But the reverse is also true: a good diet reduces cardiovascular risk even in physically inactive individuals. The PREDIMED trial, which involved largely sedentary or moderately active older adults with cardiovascular risk factors, found a 30 percent reduction in major cardiovascular events attributable entirely to dietary change, with no prescribed exercise intervention.
What Diet Changes That Exercise Cannot
Exercise improves cardiovascular fitness, reduces blood pressure, improves HDL cholesterol, and reduces visceral fat. Diet changes the lipid particle composition in the bloodstream, reduces LDL particle number and oxidised LDL, reduces systemic inflammatory markers, improves endothelial function through nitric oxide production, and changes the gut microbiome in ways that affect systemic cardiovascular risk. These are different mechanisms. Combined, they produce additive risk reduction. Relying exclusively on either at the expense of the other produces suboptimal cardiovascular protection.
The Dietary Levers for Cardiovascular Health
- Replace refined vegetable oils with extra-virgin olive oil: reduces LDL oxidation, improves endothelial function, reduces platelet aggregation
- Increase soluble fibre from oats, legumes, and psyllium: reduces LDL cholesterol through bile acid sequestration
- Increase oily fish to two to three portions weekly: EPA and DHA reduce triglycerides and inflammatory eicosanoids
- Eliminate sugar-sweetened beverages and processed meat: remove the primary dietary pro-inflammatory and pro-atherogenic inputs
- Include nuts daily: reduces LDL and improves endothelial function through arginine, plant sterols, and polyphenols