To determine whether or not someone is healthy is a hard task on its own. An educational website, "Pursuit", says, "... In order to know someone is unwell, we have to know how they [differ] from normal. Then, in order to work out if someone is getting better we have to know that we’re returning them to normal. And finally, to know that someone is well, we have to know what normal is." This means that to be in a normal healthy state differs from person to person, and is something difficult to pinpoint. However, on the bright side, the medical field is constantly improving and expanding information and references to understand what is normal and to treat and diagnose patients better.

Ignjatovic, Vera, et al. “How Do You Define Healthy in Kids?” Pursuit, The University of Melbourne, 13 Nov. 2018, pursuit.unimelb.edu.au/articles/how-do-you-define-healthy-in-kids.