Subject: Is there a 'point of no return' age for being able to grow facial hair?

I am 23 and cannot grow much facial hair.  I realize that this is most likely 
due in part to a lack of testosterone, however I have also read that an 
abundance of DHT can cause this problem too.  Is there anything that can be 
done, or should I give nature another year or two to kick in?

Re: Is there a 'point of no return' age for being able to grow facial hair?