Safah is Fatphobic
I believe her anxiety about Farhad's health, for wherever reason, is real, but the way she talks about his body is disgusting. Trying to push him into a surgery! For 120kg! Bariatric surgery is a last resort when you are so fat that you might die from obesity-related complications before you can lose it naturally. It has big risks, and can take years off your lifespan. And most importantly, IT IS HIS BODY AND HIS CHOICE.
I realize he tries to make decisions about her body, too, with his fanatical obsessions with trying to have a son, but it's never ok to control another's body.
If Safah were 120kg and Farhad spoke about her weight like this, the doctor would have reported it to a social worker.