The process of ejaculation in general affects ones hormones so I would say its orgasming that has to do with it. Whether or not someones T level is affected by orgasm would depend on their genetics and how their hormones are affected by masturbation.
my question was whether it is watching porn that is causing low T or masturbation that is causing it since generally people who watch porn also masturbate, so im trying to find out the true source
Yeah, I know. I would assume its masturbation that causes Low T since masturbation can fluctuate ones hormones. I've seen studies that say estrogen and prolactin levels go up after masturbation and T levels start to go down. As far as I know and have heard watching porn and/or getting horny however, actually seems to raise T levels. Of course that dosen't mean watching porn is a good thing( we all know about the website yourbrainonporn), that raise in T level is just sexual energy building up in the groin area. I've heard of athletes using sexual stimulants before games because it gives them a huge burst in energy which they transmute during the game. I reccommend you check out the book "Cupids poisoned arrow" to understand how masturbation can affect someones hormones.
Fapping to porn lowers the level of testosterone on the other hand sex increases the level of testosterone
It makes total sense. Porn messes our mind and also our hormonal balance. Need to rebalance testosterone in my system