I honestly never thought about that but if I were to guess I would say he definitely has ADHD. He is impulsive in his action against other people, doesn’t listen to what his crew tells him. He also switches between thinking about food, meat and becoming the pirate king. Plus all that jumping around and acting jittery is an everyday business.
only do something dangerous and health risking on your days off
The best test would be a BMI. Hydrostatic weighing would just find their weight and wouldn't tell the doctor anything about the specific amount of fat on the body. There is no such thing as an MRK, and the Caliper test is a personality test. I hope this helps!