The most visible sign of the hormonal effects of drinking is brewers droop, the very reason why a man often has erection problems after drinking.
I'll explain the mechanism.
Drinking lowers testosterone and increases the aromatization of androgens to estrogens. (this is partiularly true of beer which contains phytoestrogens).
This then causes a reduction in the bodies production of N.O and N.O is required by the body to produce and maintain an erection (viagra increases N.O).
Of course this hormonal change can increase gynecomastia, although gynecomastia is usually the result of more permanent hormonal changes.
On which note;
Excess alcohol intake can cause a permanent change in hormone levels and result in permanent hypogonadism, which in tern often causes gynecomastia.
It is surprising how strong a poison to the testis alcohol is. It may be directly or through its intermediate breakdown product, acetaldehyde or by increasing SHBG (sex hormone binding globulin) the carrier protein for testosterone and estradiol.
Either way even in a moderate drinker, blood testosterone levels fall as alcohol levels increase. Drinking enough to cause a hangover has been found to lower testosterone levels 12 to 20 hours after drinking, in one study to 20% of their levels before drinking. It has been suggested that sagging hormone levels may be one of the reasons why a hangover feels so awful.
This might explain those eye opening hangover cure such as prairie oyster based on boosting cholesterol levels with raw eggs, given that cholesterol is the building block that the body uses to make testosterone.
alcohol can cause long term testicular damage and its short term action in reducing testosterone levels and erectile function, alcohol can take away both desire and performance in men.
The first thirty percent of Malcolm Carruthers M.D (endocrinologist) hypogonadism patients reported drinking more than 21 units a week and as stated hypogonadism often causes gynecomastia.
A quote from Malcolm Carruthers M.D endocrinologist in quoting someone else.
A sixteenth-centuary physician called Cornaro wrote "the excesses of youth are like drafts upon our old age, payable with interest about twenty years after the date. This is certainly true in relation to alcohol.
So not only can alcohol cause gynecomastia via hypogonadism but it can also cause gynecomastia via liver problems.
18% of gynecomastia sufferers either have hypogonadism or liver problems for which alcohol would be a problem.
Being tee total has its own drawbacks, so perhaps drinking less than what is termed moderate- as in a little every now and again is a good idea.