When I first googled "Weight loss support" 3FC was one of the first sites that popped up. I am sure many other people in my life have done the same, or similar search online and saw the same search results. 3FC is not a hidden website that it took me hours to find. I find it really, really hard to believe that no one I know in real life is actively using 3FC or at least reads it frequently.
Though I haven't posted my name or a picture on here, I have posted enough on here about my current situation to where many people who know me in real life could figure out who I am. I therefore do not post any information I wouldn't be mortified/upset for others IRL to find out. This includes personal relationship information, photos, intimate details about myself, etc.
If someone IRL were to figure out who I am I would be a little disappointed I lost some sort of anonymity, but I wouldn't be embarrassed because I have kept boundaries on 3FC. If you are as private as I am about weight loss, I'd be careful about posting pictures that show your face, easily identifiable clothing (a t-shirt you always wear), or a setting that is obviously your house. And I wouldn't post any information that would be devastating to you for others at work or in your social circles to find out.
Many people have no qualms about this, which is great. I do and it seems like you do too, which is why I'd suggest being careful. It's not being paranoid, it's being smart and realistic about how likely it is others have stumbled across this website.

People who don't me...that really doesn't bother me at all. But people who knew me when I was much thinner? Oh yeah, that bothers me.
So I simply don't risk that kind of embarrassment. 

