In male patients with coronary artery disease, replacing refined rice with whole grain and legume powder for 16 weeks reduces plasma malondialdehyde and urinary 8-epi-prostaglandin F2α concentrations by approximately 28%, indicating a significant reduction in systemic lipid peroxidation and oxidative stress.

When people eat whole grains and legumes instead of refined rice, their blood sugar rises more slowly, which tells their pancreas to release less insulin. Over time, this makes their cells more responsive to insulin, which lowers the amount of free radicals produced in their body. At the same time, whole grains and legumes provide natural antioxidants that directly neutralize any remaining free radicals. Together, these actions reduce damage to fats in the blood and cell membranes, which is measured as lower levels of malondialdehyde and 8-epi-prostaglandin F2α.