I don't tell them. I get to know them better. Anorexia or Bulimia and or some other disease could be plaguing them. 1 huge example is my aunt. She's so.....so....so..... thin you'd think she's not trying but she can't eat whatever she wants. There is something wrong with her medically and she gets allergic reactions to many foods. She does try to be healthy it's just difficult 😔 she is so sweet. I know it's easy to judge anyone. It's tough seeing someone you care for struggle with anything and you not have the solution to it.