Anabolic/androgenic steroids are most consistent in their lowering of HDL levels. This adverse effect is mediated through the androgenic stimulation of hepatic lipase, a liver enzyme responsible for the breakdown of HDL (good) cholesterol. With more hepatic lipase activity in the body, the favorable (anti-atherogenic) HDL cholesterol particles are cleared from circulation more quickly, and their levels drop. This is an effect that seems to be very pronounced at even modest supratherapeutic dosage levels. For example, studies with testosterone cypionate noted a 21% drop in HDL cholesterol with a dosage of 300 mg per week. Increasing this dosage to 600 mg did not have any significant additional effect, suggesting that the dosage threshold for strong HDL suppression is fairly low.
Oral steroids, especially c-17 alpha alkylated compounds, are particularly potent at stimulating hepatic lipase and suppressing HDL levels. This is due to first pass concentration and metabolism in the liver. A drug like stanozolol may, therefore, be milder than testosterone with regard to androgenic side effects, but not when it comes to cardiovascular strain. A study comparing the effects of a weekly injection of 200 mg testosterone enanthate to only a 6 mg daily oral dose of stanozolol demonstrates the strong difference between these two types of drugs very well. After only six weeks, 6 mg of stanozolol was shown to reduce HDL and HDL-2 cholesterol levels by an average of 33 and 71% respectively. HDL levels (mainly the HDL-3 subfraction) were reduced by only 9% in the testosterone group. LDL cholesterol levels also rose 29% with stanozolol, while they dropped 16% with testosterone. Esterified injectable steroids are generally less stressful to the cardiovascular system than oral agents.
It is also important to note that estrogens can have a favorable impact on cholesterol profiles. The aromatization of testosterone to estradiol may, therefore, prevent a more dramatic change in serum cholesterol. A study examined this effect by comparing the lipid changes caused by 280 mg of testosterone enanthate per week, with and without the aromatase inhibitor testolactone. Methyltestosterone was also tested in a third group, at a dose of 20 mg daily, to judge the comparative effect of an oral alkylated steroid. The group using only testosterone enanthate in this study showed a small but not significant decrease in HDL cholesterol values over the course of the 12-week investigation. After only four weeks, however, the group using testosterone plus the aromatase inhibitor displayed an HDL reduction of an average of 25%. The group taking methyltestosterone experienced the strongest HDL reduction in the study, which dropped 35% after four weeks. This group also noticed an unfavorable rise in LDL cholesterol levels.
The potential positive effect of estrogen on cholesterol values also makes the issue of estrogen maintenance something to consider when it comes to health risks. To begin with, one may want to consider whether or not estrogen maintenance drugs are actually necessary in any given circumstance. Are side effects apparent, or is their use a preventative step and perhaps unnecessary? The maintenance drug of choice can also have a measurable impact on cholesterol outcomes. For example, the estrogen receptor antagonist tamoxifen citrate does not seem to exhibit anti-estrogenic effects on cholesterol values, and in fact tends to increase HDL levels in some patients. Many individuals decide to use tamoxifen to combat estrogenic side effects instead of an aromatase inhibitor for this reason, particularly when they are using steroids for longer periods of time, and are concerned about their cumulative cardiovascular side effects.
Wlliam Llewellyn (2011) - Anabolics