Roasted coffee is better than green coffee at protecting liver cells from damage caused by harmful chemicals in rats, because roasting makes the coffee compounds more powerful at fighting this kind of damage.

Coffee that’s been roasted and made acidic might contain tiny natural compounds that help protect the liver from damage caused by harmful fats.

When coffee is roasted really dark and treated with acid, then soaked in a special solvent called ethyl acetate, it pulls out chemicals that do a better job of protecting fats in your body from damage — and those chemicals only form during dark roasting.

Unroasted green coffee beans have a bit more antioxidant power in lab tests than roasted coffee beans, which means roasting might weaken some healthy compounds but make others stronger.