Secoisolariciresinol diglucoside (SDG), also known as secoisolariciresinol diglucoside, is a natural plant lignan diglucoside primarily found in flaxseeds (Linum usitatissimum) and sesame seeds. It acts as the main dietary precursor to the mammalian enterolignans enterodiol and enterolactone via gut microbiota metabolism. As a high-purity (≥99%) specialty chemical reagent, SDG is widely used in biochemical and pharmacological research to investigate lignan bioavailability, phytoestrogenic effects, antioxidant mechanisms, and hormone-related pathways.

It is renowned for its potent antioxidant properties, which neutralize free radicals and mitigate oxidative stress. Studies highlight its role in cardiovascular health by lowering cholesterol levels and enhancing heart function. SDG also demonstrates anti-inflammatory effects beneficial for chronic conditions, potential inhibition of cancer cell growth (particularly breast and colon cancers), and preliminary evidence for blood glucose regulation in diabetes management. Consequently, it is incorporated into dietary supplements for overall wellness and disease prevention.