Hi gypsiemama,
Like you, I was always very thin until after my third child. It's more challenging to keep my weight down than it was before, but with raw and regularly exercise I can do it.
Here's a site that might interest you. If you are obese, you do have to watch the fat intake as on raw it's easy to go overboard with all the nuts and oils.
http://www.ibeatobesity.com/
Here's another raw obesity site:
http://www.rawreform.com/
All the best to you!