"Most of the investigations have been focused on risk factors for cardiovascular diseases, and in particular the effect of anabolic steroids on blood pressure and on plasma lipoproteins. In most cross-sectional studies serum cholesterol and triglycerides between drug-free users and non-users is not different. However, during anabolic steroid use total cholesterol tends to increase, while HDL-cholesterol demonstrates a marked decline, well below the normal range. Serum LDL-cholesterol shows a variable response: a slight increase or no change. The response of total cholesterol seems to be influenced by the type of training that is done by the athlete. When a great deal of the exercise consists of aerobic exercise, the increasing effect of AS is counterbalanced by an exercise-induced increasing effect, which may result in a net decline in total cholesterol. Aerobic training does not seem to be able to offset the steroid-induced decline in HDL-cholesterol and its subfractions HDL-2, and HDL-3.
The precise effect of anabolic steroids on LDL-cholesterol is unknown yet. It appears that anabolic steroids influence hepatic triglyceride lipase (HTL) and lipoprotein lipase (LPL). Males usually have higher levels of HTL, while females have higher LPL activity. HTL is primarily responsible for the clearance of HDL-cholesterol, while LPL takes care of cellular uptake of free fatty acids and glycerol. Androgens and anabolic steroids stimulate HTL, presumably resulting in decreased serum levels of HDL-cholesterol.
The effect of anabolic steroids on triglycerides is not well known. It is suggested that relatively low doses do not affect the serum triglyceride levels, while it cannot be excluded that higher doses elicit an increase."