Nanci- I really wish I had some great advise for you to help you here. The only thing that raised a red flag for me in your post was this..."My food intake has not changed." Now I'm not sure here if you're talking about the "type" of intake or the "amount" of intake. If you're talking about "amount", then I'm thinking with losing 50 pounds, it would have to change, as you're supporting much less weight. ( A big CONGRATS on that BTW). I know for myself that in order to lose, I have to watch calories. There are many that don't, but unfortunately, that's not me. It might be helpful to post some menus so that others may be able to see some potential trouble spots! Also..look for things that are different in your life..such as hormonal changes that may be going on, medications or supplements that may have been added. It might not have anything to do with this WOE or exercise!