What is the average weight of a 18 year old?

Appropriate weight: Appropriate weight is no longer used. We ogo by body mass index that takes into consideration, height, age and physique of the person. You should talk to your doc next time you go see him/her.

Depends: The average is not the best way to look at the proper weight, as the health weight for an 18 year old depends on height and sex, and to some degree muscle mass, so a 5'3 18 year old gymnast and a 6'3 18 year old tight end on the football team and a 5' 7 18 year old chess player all would have different healthy weights. I am not sure an average is meaningful.

Depends: It depends on height. Would need to know the height to give an estimate average weight.