What causes hair loss?

I'm young but I am curious because my dads head is shedding hair.What causes hair loss?
Stress and genetics.What causes hair loss?
There are so many answers to this question. Personally I think you should have given more information to help get an answer to your question. Is your father on medication? Does alopecial run common in your in your family? Is he using in chemical on his har? Is he sick? How old is your father? Is he stressing or worrying about anything? All of these things can add to hair loss.
Lack of adequate sleep and lack of Nutritional food would results in hair loss.



Stress also cause hair loss.



Some may be affected by Genetic problem.



The below link is useful for you to avoid hair loss.



http://www.atozanswer.com/forum/viewtopi/a>
Genetics. That's it.
genetic and testosterone
Shaving.