Its late and we have answered this question a few times today, so forgive me for copying and pasting this answer from another question:

One thing people forget is that both clomiphene and enclomiphene block IGF-1. IGF-1 is a very, very important hormone for muscle gain and fat loss. In fact, it is the primary reason you gain muscle mass with weight lifting. Blocking IGF-1 has been proven to decrease muscle mass and increase adipose tissue.

Here’s a study that shows how 6 weeks of using enclomiphene will lower IGF-1.

In the study, multiple patients’ plasma concentrations of IGF-1 decreased over 50%. Compare to another SERM, let’s say tamoxifen and clomid, plasma concentrations of IGF-1 decrease by a mean of 28.5% and 31%, respectively.

So clomid and enclomiphene are used off label for hypogonadism. They help with many of the symptoms of low T including fatigue, low libido, anxiety, and mental focus. However, they paradoxically decrease muscle mass by blocking the anabolic hormone IGF1.

TL;DR: Low testosterone causes loss of muscle mass, but clomiphene and enclomiphene causes further loss of muscle mass by blocking IGF-1 production. Higher muscle mass and lower adipose tissue prolongs life and reduces chronic disease. TRT increases both T and IGF-1 and has long term studies proving its safety and benefits to overall health and reduced incidence of disease.