You have not mentioned your height and the amount of weight lost by you.
Please take out from your mind wrong notions regarding masturbation
and the ill effects it has caused to you.
masturbation is a perfectly normal phenomenon and it doesn't cause any harm to you.There are plenty of myths and wrong education in our society regarding masturbation.
These myths and wrong notions create a sense of guilt in you and you become a victim of your self created doubts.
Your hands don't thin out by doing masturbation.
I am quite sure that you are a perfectly normal individual with no problems and this weakness you are complaining is more of psychological in nature rather than physical.
Do regular exercises and take green vegetables,fresh fruits,dry fruits,chicken,fish and eggs in your diet.
Avoid alcohol and smoking
Enjoy your life and concentrate on your career.
Thanks and best of luck.