How can smoking cause increase of cholesterol?

Lowers HDL: Smoking appears to decrease good HDL cholesterol with little consistent effect on the bad LDL cholesterol. The lower levels of HDL will increase the risk for heart attack and stroke. It is difficult to treat low hdl, other than stopping smoking. Smoking also has multiple other bad effects including cancer, copd, erectile dysfunction, and irreversible accelerated skin wrinkles and aging.