My 14year old has been eating a lot of fast food latley, is he at a higher risk for getting a stoke or am i paranoid?

Easy does it: Being a 14 year old boy is difficult enough and he has pressures to fit in with his peers. If you make big deal out of his perhaps getting a stroke later (he has plenty of time to improve his habits without damaging himself), he will not (and probably should not) accept it. Enjoy having a teen while it lasts, and as long as he does not start smoking or try meth or cocaine, he won't ruin his health.

Habits start young: While it is normal for many teens to crave the immediate gratification of fast food, developing life long eating habits start now. While he is in no imminent danger, eating fast foods too much can lead to weight gain, poor nutrition, high cholesterol etc. Talk to your teen about developing healthy habits to avoid becoming an overweight adult. And eat healthily yourself. It will have an impact!