In my first point in my post "Online Security Starts with You! healthunlocked.com/cllsuppo... , I mentioned the advisability of choosing a different username for each site you joined if you particularly valued your privacy. I've just noticed that HealthUnlocked are able to change your username for this site if you wish. Naturally you may not get your first choice of an alternate name if it is already taken, but I for one am impressed that HealthUnlocked provide this service.
Changing your Username:
More on the new Help Pages: