I am naturally slim can i still be a cop?

HI i got a question i want to be a cop but i am a skinny guy i weigh 150 pound's and i am 6'1 i am 21 i am currently in college taking criminal justice courses for law enforcement i want to be a state tropper when i graduate i goto the gym but i dont see any increase in my body size the dr said ill always be a skinny guy and someone told me i will get disqualified because i am a skinny dude is that true?