Information from the Nurses' Health Study indicated that the combination of estrogen and androgen used to treat hypoandrogenism could increase breast cancer risk. However, other studies indicated androgens may decrease breast cancer risk. Follow-up studies on the Women's Health Initiative found women who received estrogen and no progestogen showed a significant decrease in cardiovascular disease (CVD) and breast cancer. This has caused a reconsideration of androgens added to estrogens. Still, the FDA requires demonstration of CVD and breast cancer safety for any product containing androgens or estrogen plus an androgen; that has not been done.
Side-effects are not expected because testosterone therapy aims to bring a man’s testosterone levels back to normal. However, testosterone therapy can increase the growth of the prostate gland which can make the symptoms of benign prostate enlargement (such as needing to urinate more often) worse. In the case of prostate cancer, testosterone therapy is not used because of concerns that it can make the tumour grow. Too high a dose of testosterone can lead to acne, weight gain, gynaecomastia (breast development), male-pattern hair loss and changes in mood. Any side-effects should be managed by a doctor and the testosterone dose lowered.
In the Oxford Journal of Gerontology Series A: Biological Sciences and Medical Sciences, the popular nonsteroidal SARM LGD 4033 (Ligandrol) has been recently studied for it’s effectiveness and safety in healthy young men. Results were favorable indicated by hormone and lipid levels returning to normal without the use of a post cycle therapy. No dangers were detected throughout the study. although there was noticeable suppression in testosterone and HDL cholesterol, it was not significant enough to cause adverse reactions. Because LGD 4033 is considered one of the strongest and most potent nonsteroidal SARMs available, it is not likely that less potent SARMs will produce any harmful effects (Bhasin, 2010).