Yes, your friends will wish you well, say good luck, and then just hope that you stop talking about it. Facebook is a place for friends. It's a place for close friends and family. They love you, but they don't love hearing you talk about your new company that promises weight loss and fitness.
But wait a minute, there are lots of people who are interested in your business. There are millions of people out there who would love to know about your product, and how it will make their life better. But you need to step away from Facebook.
The place to go is Google+. And the way to do it is to present publicly. The people who read your posts, and about you and your business (mine is one and the same - it's just me) will not be your friends who are just standing on the sidelines cheering you on, they will be people who are genuinely interested in your product or service.
No, I'm not recommending leaving Facebook, although I've tried it. It's kind of like trying to kick junk food, sometimes it just feels to good to resist. But if you are building your business, and want to get the word out to the largest possible audience, and stop annoying your family and friends, move that stuff over to Google+.
See you on Google+. I am interested in learning more about your product for weight loss.