Policosanol is an extract from the waxes of sugar canes. It is known for it's ability to  break down low-density lipoprotein (LDL or "bad") cholesterol while promoting the increase of high-density lipoprotein (HDL or "good") cholesterol. 

LDL cholesterol is considered a "bad" cholesterol because high LDL levels lead to a buildup of cholesterol in the arteries. HDL cholesterol is considered a "good" cholesterol as it helps carry cholesterol from other parts of the body back to your liver, where it can be removed from the body.