This claim has been floating around for years and the best evidence for it is probably that Trump hasn't said anything or taken any action on defamation or libel.
That said - I have absolutely no desire to defend Trump (and not targeted at you
@BlueMoonAcrossThePond) but this whole line of attack makes me feel immensely uncomfortable. There are plenty of people out there (more than you would probably suspect), who struggle with bowel problems every day, whether it's crohn's or colitis or the impact of cancer. And as somebody with personal experience it is probably one of the worst problems you can have when it comes to public understanding - nobody understands it unless you have to deal with it. It's seen as taboo to mock somebody in a wheelchair, but somebody with bowel problems is totally fair game. I've had full on arguments with blues who feel it's okay to make fun of Darren Fletcher because of his ulcerative colitis. I get that people will say this is fair game because it's self-inflicted by drugs, but it's more about the impact mockery like this has on those fighting these battles day-in day-out. Again, you wouldn't mock somebody in a wheelchair, even if the reason is self-inflicted.
There are plenty of reasons to hate Trump and to think he is totally unsuitable for the role of President, bringing his physical health into it for me is only as relevant as to how much it prevents him from doing the job. Let's not be so quick to cede the moral high ground just because we hate somebody this viscerally.
