Exercise will increase your HDL, get your doctor's advise on a good cardio program to increase your HDL. Also, fish out helps so find a good fish oil made from cold water fish and gives you at least 600 MG of Omega 3s per day. Make sure you run it past your doctor as well.
I know that in the UK researchers are pushing for statins to be prescribed to virtually all ages to give people a head start preventing heart disease. I heard one cardiologist say how atherosclerosis starts early, in many teenagers. I guess until society becomes an easier and happier place to live in, any measures would be beneficial. If you are worried about anything, I would have a chat with your Doctor about it because they are connected to all latest research results.