Munchkin:
Calories mean nothing to us anymore. Can you post up what you eat in terms of protein grams, fat grams and carb grams, be honest and we will have a look.
I have a 75cm cc and as long as most of my intake is protein and fat (I do eat about 150g of carbs too), I maintain without thinking about it and my calories are around the 2800 mark. I only know this as I use MyNetDiary. Eating 800 cals a day would in my eyes be highly dangerous for a DSer....150g of protein is 600 cals alone and that's the minimum, then you should be getting at least (minimum) 70g of fat a day, that's another 610 calories.....if I want to drop weight I up the protein and fat (up from 150g to 200g and 100g to 150g respectively) and cut carbs.
I'd guess that you aren't eating enough fat....a lot of DSers don't eat enough, but what they don't realise is, we malabsorb fat and, just like protein, it's essential for healthy body function, but because we malabsorb it so much more than protein, we therefore need to stuff our faces with it to end up with any at all absorbed!
I used to say calories mean nothing to us just like you. Protein and fat are like free foods. And it used to be true for me just like it is for most. I am a superabsorber. I got my first diet at 6 weeks old. The DS was never a free ride for me. I had no problem at all with the surgery, that was easy for me. The problem was weight loss.
My high weight was probably close to 400lbs. I had to wait for the DS for 2 years. I was so pissed off with myself my new motto was "Thin or dead. Either one is just fine with me." I even started practicing psychological warfare, I had to tell myself food is not your friend every time I took a bite. So one last diet. 2 cans of tuna and 2 cups raw spinach. And a vitamin. Every day for 2 years while I waited. I did take off for my birthday and holidays. About 10 days a year. I went into surgery officially a lightweight at 251lbs. In the first 6 months I lost down to 200 and that's it. 3 more months passed...no loss.
I got desperate. I didn't go through all this to still be fat. I had been walking 5 miles a day and I hated taking the time for it. So after spending some time with couch to 5K, I started running. Running made a big difference. Over the next year or so, I got down to 160 and even though I wasn't really thin that was OK. That was the beginning of my 'good' years. As long as I remained active and was aware of carbs, I maintained pretty well. ONCE, I even got to wear a pair of size 6 non-stretch jeans. Once. The muffin top was horrible. More like the whole loaf, but I got those jeans up, zipped, and buttoned.
In 2009 I got a hernia I can't afford to fix so no more AB work. And I'm getting older. Past 60, running equals injuries. Plus I now live in Vegas where it's too hot to run for miles in the extreme heat. I do still run some from October to May. But not the 30 miles a week I used to do. My fitbit tells me I am still active enough that I should be able to maintain and I have been doing a lot of physical work remodeling my house.
Around 2011 something changed and I can no longer maintain on the usual DS diet. I have a very efficient body and it doesn't waste anything. And BTW even with my supposed 75 CC, I have never had any deficiencies and never needed infusions or had to take drastic measures to keep my labs in line. No osteoporosis here either. I CAN take gelcaps too.
Summer is winding down here. In another month or so, daytime temps should be under 100. I have a lot of really physical jobs saved up like removing tree stumps and moving rocks. Plus I will start running again. And then the diet begins. 2 cans tuna, 2 cups raw spinach and perhaps in deference to whatever is left of my DS, I will put some ranch on the spinach and add a no carb protein drink. Yeah, I know I'm whining but it's really hard to eat like this in Vegas! I just need to go back to my old mindset.