Wii fit alone won't take the weight off, so you'll also have to regulate your diet to help it along. I found an online community that allows you to keep track of your water intake, your food intake, provides suggested meal plans from day to day, offers a grocery shopping list for the week and a lot of other people out to do what most of us are trying to do: get healthy.
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Much like Wii Fit, you can also earn points daily by keeping your food journal, reading articles, logging your exercise, etc.
I just recently began using it in conjunction with Wii Fit, and I invite you to do the same. And I also suggest finding another activity to enjoy as well. I bellydance, what do you do?