I've read that masturbation and porn can cause general feelings of anxiety and low confidence and self esteem. In general it can cause social anxiety and seclusion from the real world. When I read this I identified with it and have actively tried to change my ways.
Im not saying that people who are happy in themselves and have perfectly normal relationships should not masturbate. THere is a place in life for masturbation but I do think that if you are going through social anxiety problems then masturbation does not help. Obviously I can only comment from my own situation.
It particularly the aspect of spending time watching porn and continually satisfying desires that really should be satisfied by conducting meaningful relationships with women.
In short masturbating is just preventing these relationships being formed because when you relieve the tension you no longer have the desire to actively do something about being single.
Over the last couple of months I decided to stop masturbating and looking at porn to see if it changed my feelings. I can say that overall I felt more motivated to go out and do things that would help me meet women. I also felt less anxious than normal, perhaps because I was no longer shamed at what I was doing not that theres anything wrong with masturbation.
But I would say that since I've stopped it has helped in other aspects of my life. It does get very difficult even after a few days but I've learned self control and managed to resist the urge. I did have to have one after 2 weeks but I just almost did it to stop the pressure building and I didn't feel so bad afterwards because I then waited another 3 weeks.