Question: Is growing your hair out unhealthy in anyway if you are a teenage male?
Answer: No, growing your hair out as teenager does not lead to hair loss, if this is what you meant. The length of your hair does not affect its health in anyway. Hair grows in cycles with each strand having a lifecycle independent of the other hairs. The hair sheds once it has reached its end of lifecycle. This explains why we lose hair everyday yet we still maintain a head of hair. The longer your hair, the more you notice the hair coming out as it gets trapped in the bath plug or it gets stuck in your clothes. To summarise, hair can be healthy even if you keep it short or long.
It is important to regularly check your hair for signs of hair loss though, because male pattern baldness can start early for some men. Most men will see the early signs (a receding hairline and loss of hair from the crown) in their 20s or 30s however for some it will begin in the teens. For others it will develop later in life. As soon as you notice any changes, it is advisable to get your hair checked out so you know what is causing the hair loss. The earlier that genetic hair loss is treated, the better the results that can be achieved.