How can i lose my tan?

um i was born white but over the years of wearing short sleeves my arms got tan nothing else my face is pale my body is pale my legs are pale its just my arms and i just wanted to know if u can get rid of years worth of tan but i just want to make it as light as i can im from puetro rico but im a white puetro rican if that makes a difference i do wear a jacket every day but it doesnt seem to fade? can u please help =]