Synthesis Writing. Although at its most basic level a synthesis involves combining two or more summaries, synthesis writing is more difficult than it might at first appear because this combining must be done in a meaningful way and the final essay must generally be thesis-driven.
1. Endocrine Diseases. The bodyâs endocrine system produces hormones that regulate metabolism, sexual function, reproduction, mood, and much more. Diabetes is an example of an endocrine disease that can cause men to experience impotence. Diabetes affects the bodyâs ability to utilize the hormone insulin.
Sexual dysfunction in men. 1  Diabetes can cause nerve and artery damage in the genital area, disrupting the blood flow necessary for an erection.  Some men with diabetes experience retrograde ejaculation, which means that the ejaculate goes backward into the bladder instead of being discharged during climax.