Cossy
It’s never, ever ok to tell anyone that they are too large/thin/spotty/scruffy We don’t need to comment on people’s weight or appearance.
Does anyone actually tell another that they are "too fat" though (apart from those who enjoy being spiteful)?
Wouldn't a well-intentioned friend be more kind, or diplomatic (not that I'm recommending this approach)?
My ex-DIL told me once, post surgery, that she thought I wasn't eating enough to maintain my weight, and that she was worried for me. She didn't say, "you're too thin". It was obvious that she and my son had been 'talking' - he'd probably encouraged her to 'say something'.
I wasn't offended, I knew they both cared. And they were right - I left hospital and hit the ground running because my disabled OH was deteriorating and I spent my energy and time on him. I was in fact grateful because it made me take a look at myself. They followed up by offering practical help, too.
Some might think that being thin is no big deal - you don't really get the stares, whispered comments, etc, that overweight people sometimes have to suffer. But - I did look pretty awful nevertheless.
The hospital were badgering me because I was losing weight, and they wanted to do an assessment. Fortunately, my DIL's intervention was a wake-up call, and the practical help allowed me to start to get back on my feet again.
So, my point is, is it always a bad thing to take an interest in someone else's 'appearance' if you think they are maybe doing irreparable harm to themselves, you care, and are in a position to offer practical help? With the caveat that you really do have to know that person very well, and really care about them.