Should I tell my coworker they smell?

It depends on how well you know them. Maybe she would be glad that somebody had told her but maybe she'll be upset. If she doesn't go to the bathroom somethings up

I have a similar problem before, my new co-worker is also my new friend and she has no body odor but she has a bad breath. I've been planning for days to tell her but I just can't bring myself to do it. It's really a problem for me because she's my friend and I don't want other people to notice or smell and make fun of her behind her back. There's a lot of backfighters and gossipers in the office and I'm afraid they make her a new target. What I did was I inserted an anonymous computerized letter in her drawer. I don't know if she suspected me for doing it, she showed no signs and she didn't ask me. I resigned from work, and we don't get to see now so I don't really know what's the result. I just wish she followed my advice that she consults a dentist.