how do i convince my parents that i need a haircut?

How can I convince my parents that I need a haircut? They say no because I'm from a Sikh family but I don't believe in religion. Because of the type of lifestyle I have, my hair has to be tied tightly for quite some time everyday and I'm starting to bald from the front. I went to the doctor and he also told me to get it cut my dad said no. He says that it would hurt my grandparents a lot if I cut it because they are very deeply religious. It's interfering with my life and I jut want to get it cut. I'm 18 but I don't want to do without telling my parents coz I love them a lot. What do I do?

same story man but in mine my father isn't allowing me because of his faith

well my dad wont let me do a side maheecn and I say that I want it and he said no you will have short aack and side

QUOTE who"badman"]well my dad wont let me do a side maheecn and I say that I want it and he said no you will have short back and side so I cutted my hair bymyself and he got mad man it was funny and he said next I will let you do a maheecn come on I will take you to the babers and I was happy the side maheecn I was good looking