Is my fat my own feminist issue?

I have blogged before some of my before and after progress pictures as well as why I have no clue what I weigh or measure, and how I changed my ingrained habits.

So currently I'm perhaps the smallest I've been, but still pretty hourglass (yey).  I haven't been keeping up to the gym as much as I'd like, but life got a little busy, but I'm still going when I can. I say no more often than yes, and I sometimes have quite conflicting emotions about it.

An odd part of my brain feels I'm some how letting the side down, when I used to say yes to all the cake, all of the time, I somehow thought I was showing the world that I deserved the cake. It was my treat, and I was worthy of treats all of the time.

However, actually, being smaller, and eating tons more fruit and vegetables is a much bigger reward. I deserve to be healthy and fit. I deserve to give my body the right nutrients, and actually I deserve to be slimmer.

I'm not on a diet, and I don't count anything, but I choose saying no more, for ever. My life, and my body are better through learning I don't need to 'reward' myself with constant cakes, pizzas and biscuits. I don't feel deprived, I just feel better.

Can a feminist believe that slimmer is usually healthier and a better choice? Our own fat is such an emotional issue, it can be hard to debate it without being enmeshed in our body concerns. Why do I feel a little guilty about saying no and being smaller? Interesting for me to ponder. Would love your thoughts so I can write something a little more concise!