I'm 5'5", 39years old and weight 54.31kg. People look at me like I'm anorexic and ask me if I eat. I eat like a lumber jack.

You sound pretty thin, I definatly wouldn't loose any weight if I were you. Are you a good biker or do you have a hard time following others? I bike a lot and run 8km every other day. I have a hard time keeping weight on. Bikers are thin because ofcourse the lighter you are, the faster you go, but they also have very muscular legs.