Because they all love the diet since it caused them to lose weight.

My SO has been on it for a couple years. He LOVES it and swears by it. He's lost over 100 pounds. Also, now his breath and shit smell like death, he goes back and forth from constipation to diarrhea throughout the week, has frequent headaches, and his BUN and creatinine levels are elevated. But he doesn't care. He posts regularly on the keto subreddit giving out advice and talking about his weight loss success.

I've tried talking to him, but everything I say gets dismissed because I'm "just a nurse". Even when I tried telling him what registered dieticians think, he laughs it off as propaganda from farmers. The next time I see his bloody poop on the toilet, instead of cleaning it like I always do, I think I'm going to take a picture and post it to r/keto and ask what their no-carb thoughts are about that.