nutrisystem

https://community.myfitnesspal.com/en/group/discussions/7404-nutrisystem-mfp-chapter

http://community.myfitnesspal.com/en/group/105493-nutrisystem-group-users

There may be more. I googled myfitnesspal nutrisystem and those were the first two.

I lead a group of NS members. We're called Dump That Rump. If you'd like t learn more about our group, just PM me and I'll let you know the guidelines (it's a challenge group, but we're mostly about support and encouragement; the challenge part just adds a little fun) so you can decide if you'd like to join us.