This varies from person to person. There is a point in time at which hormones in a persons body begin to loose their effective functions, a period I have heard reffered to as adult puberty. In women this is marked by menopause. While you can still theoretically maintain a healthy body at this time, it becomes increasingly difficult. Maintaining a healthy diet and constant exercise are essential to achieving this. A doctor won't tell you much more than this.
Bulimia is an eating disorder in which someone forces vomiting in order to lose weight.
Therefore, I believe the answer would be throwing up after meals, as well as his teeth being discolored and his cheeks being swollen as a result of his bulimia.
Answer:
It helps people prepare for situations that can come unexpectedly so they know what to do and how to act
