Is creatine safe for body building if you are 16 and your shoulders are not broad as you want them to be wil your shoulders broaden?

Yes. There is no scientific evidence that the short- or long term use of creatine monohydrate has any detrimental effects on otherwise healthy individuals. A small number of people have complained of short-term headaches from taking too much and not drinking enough water throughout the day however, so always follow the recommended dosage.