What can friend see?

Sort of -- age and "weight to go" or how much you have lost, . . In other words -- how much more you want to lose. Not actual weight as the scale would list it. Also place/where you live if you listed it.
You can choose to keep your diary closed although most people open it to friends.
You can choose your reporting settings so that no one even knows when you lose weight or anything else if you want.
I guess you can choose how "friendly" you want to be.

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Oh, I just looked at your profile. It is already open. It shows how much more you have to go.

kickie201 wrote: »

I want to add some friends but I'm curious what they see. do they see all your personal stats, ie. weight?

You can control what people can see:
http://www.myfitnesspal.com/account/profile_privacy

http://www.myfitnesspal.com/account/news_feed_settings

http://www.myfitnesspal.com/account/diary_settings