(something) is not worth (doing something)

The phrase "it's not worth ___" is useful for telling people not to do something:

It's not worth getting upset over.

This means "You shouldn't get upset over it, because it's not that important."

When you use "not worth ___", it means that you don't think that the reward for the action is high enough for the effort or risk. For example, imagine that your friend really wants to go to a music festival. He suggests skipping work to attend the festival, even though that's a really important, busy week at work. You might say this:

I'm sure it would be a lot of fun, but it's not worth risking our jobs over.

ruin (one's) health

"Ruining" your health means doing something that makes you sick, weak, or unhealthy. Here are some things that can ruin someone's health:

• not sleeping
• eating unhealthy food
• drinking or using drugs too much

When you talk about someone "ruining" their health, it means not only that they get sick temporarily, but that it becomes difficult for them to get healthy again.

(do something) over (something)

You can use "over" to talk about the reason for someone's actions. Specifically, we use "over" to talk about negative things:

Is she still crying over what happened this morning?

I used to get upset over things like that, but not any more.