What are the differences of monounsaturated & polyunsaturated fat?

Monounsaturated fat: Both are thought to promote heart health by modestly increasing HDL cholesterol and helping to lower LDL cholesterol. In fact, replacing saturated fat and trans fats with foods containing mainly monounsaturated and polyunsaturated fats may help to protect you against heart disease. Mono comes from canola & olive oil. Poly comes from nuts, seeds, and vegetable oil.