How can I get rid of my man-boobs?

I'm 18 years old, 6'2 and around 165 pounds. I've been playing sports all my life and have a lean build. I exercise daily and hit the gym occasionally.
Despite all my best efforts I have had enlarged nipples/man-boobs since 8th grade and they play a large part in my daily life and self-image.
I honestly think I would enjoy life 200% more if I didn't have this problem...