You know I have considered this very same thing a couple of times over the years - it seems like a dream come true. And I have sort of tried it for a month or 2 at a time between jobs or school.
Here's what I found:
1 Living alone (as you do) w/out work was a very lonely experience. All my friends work or were in school so there was no one to play with during the day. And I lost the social interaction available at work.
2. Although I had time to cook, after the first week or 2 I found that all the planning, cooking, and otherwise obsessing about food was boring and to some extent self-defeating. The more I thought about food, especially the stuff I "wasn't allowed" the more I went off program and ate.
3. If I don't have a schedule that exercise has to fit in, it is so easy to say that I would do it later... and guess what? I never did.
4. I love going to the spa to be pampered from time to time. But going frequently (assuming one can afford it) also get's boring. I just need a lot more intellectual stimulation that choosing a nail color.
5. Not having something that made me feel useful or a contributor to society increased my normal inclination towards depression. Once mild depression set in, all the grand plans and goals just fell by the wayside.
In short, the experiment failed for me. I not saying that it will for you, but it probably will not be as easy as you imagine.
Maybe rather than a year, you could take a 4 week leave of absence. Or maybe reduce your work hours rather than give it up altogether. Fitting all the pieces together is really hard, but I am pretty sure you can do it with less drastic modification.
Best of luck to you - whatever the path you choose.
2.5 years, 45 pounds later... 128ish pounds