One of the best fics I've read in this vein is quickreaver's Settle Down My Shivered Bones (https://www.fanfiction.net/s/8314450/1/Settle-Down-My-Shivered-Bones). It's an eating disorder fic but it emphasizes the control aspect rather than body image. It's really really good-- the tone, the feelings, stayed with me for a long time after I read it.

And I just thought of another one-- this is teenchesters, https://www.fanfiction.net/s/3197629/1/The-Promise, where they're kidnapped and left abandoned with a limited food supply.

Thanks! I hadn't even considered teenchesters, but the fics were great, and I enjoyed them. :)

Here's an LJ link for that first fic! I strongly second both these recs btw
http://a-biting-smile.livejournal.com/920.html

I gobble up body manipulations, swapping, morphing, shifting, modifications, beefing up or getting skinny. It is SO my groove. Anyway, I have a few recs for what you're looking for (more or less; some more, some less!):

Beati Pauperes Spiritu (http://archiveofourown.org/works/2704271), by nwspaprtaxis. "Blessed are the Poor in Spirit. Post-5.03. Outsider POV. Haunted by the voicemail and Dean’s parting words, Sam seeks answers and healing only to find that those who offer him salvation have something else planned..." This one is NOT for the faint of heart! It's very detailed and creepy and OMG, poor poor Sam!

Another fic by the same author that features Sam withering away is This Far No Further (http://archiveofourown.org/works/623722). "Stabbing a Leviathan-filled angel isn't something someone can just recover from. Especially when he has a brain full of Hell before he even makes the attempt. Dean cares for his catatonic, insane little brother. And angsts. And barely copes." This one is powerful and sad and has a lot of Dean in it, but stick with it. The end is beautiful.

If you're up for longfic, I looooove A Monster By Any Other Name (http://archiveofourown.org/series/5884), by Brosedshield and LaviniaLavender. "Our story takes several steps away from canon. Dean Winchester is an only child. Mary died November 2nd, 1983, but neither in a fire nor on the ceiling. Five-year-old Sam is deported to a concentration camp for monsters. But the core remains the same. This is a love story." It's a WIP, but there's PLENTY to read! Heed the warnings, though.

Another lovely longfic is vail_kagami's And This Great Blue World of Ours (http://archiveofourown.org/works/489041/chapters/853190). "A man wakes up in a ruined wasteland, without memories, without a name, without knowing the strange guy who claims he used to be an angel, or that he once had a little brother. All he knows is that the world is dying, everyone is lying to him and that somehow, somewhere, something went terribly wrong. Because someone said Yes when they should have said No, and someone else paid the price." Finished work, fabulous world building. Love it!

The extremely talented kettle_o_fish loves to whump Sam so pretty. Here's one where a lack of sleep leads to a lack of appetite: Stand Down Son, Start Resting Easy (http://ohsam.livejournal.com/44339.html?thread=423475#t423475). I'd peruse ALL her work; it's delicious.

And there's always the 'starvation' tag at ohsam! BOOP (http://ohsam.livejournal.com/tag/starvation)


If I think of any others--because I know there are more, I just can't access them right off hand and DUMMY ME, I don't keep rec lists--I'll tack them on here. Enjoy!

So many fics! I haven't gone through the list yet, but I love nwspaprtaxis's and vail_kagami's work, so I already know I'm gonna love this.
Also, had no idea ohsam had a starvation tag! THANK YOU, you amazing creature. I feel like you've just led me to a whole new undiscovered realm here.

You're very welcome! And hey, if you find any new ones, throw 'em at me. :)

The Promise (http://samdean.archive.nu/viewstory.php?sid=631&textsize=0&chapter=1) - Kidnapped and imprisoned in a room with no exits and a very limited supply of food, Sam & Dean only have each other and their inner resources to get them through.

This is one of my favourite fics!