At this stage, it is pretty well known that negative attitudes held towards people with mental health problems (stigma) are responsible for harm against an already vulnerable group. However, such stigma is still very common, so like Winnie the Pooh wallpaper, it bears repeating. This is not about offence; although some views held can be pretty offensive, but actual harm.
A. Hotho, R. Jäschke, C. Schmitz, und G. Stumme. Proceedings of the 3rd European Semantic Web Conference, Volume 4011 von LNCS, Seite 411-426. Budva, Montenegro, Springer, (Juni 2006)