there is a prisoners study:

`` Sims was interested in whether the metabolic differences observed
between fat and thin people were the result or the cause of their body
type. Put simply, he wanted to know whether people are born fat or
made fat. He decided that the best way to sort this out was to
convince a group of slim volunteers to eat themselves fat and to
observe what happened to them when they reduced to their original
weight.

Sims was fortunate to have nearby a ready source of experimental
subjects: the inmates at Vermont state prison, sufficient numbers of
whom were willing to gorge themselves for science. At first the
prisoners proved enthusiastic trenchermen, as much as doubling their
usual daily intake of food. But as they fattened, they became
increasingly reluctant to overeat. Most found it extremely difficult
to gain weight, and eventually some started to drop out of the
study. Only 20 made it through the requisite 200 days, achieving an
average weight gain of 20-25lbs. Relieved of the high-calorie,
low-exercise regimen, all but two of the inmates quickly dropped the
newly acquired ballast. The pair of inmates who found it most
difficult to lose weight were those who had experienced the least
difficulty gaining weight in the first place. It was later discovered
that both these men had a family history of obesity.

equipped to balance energy intake and output, and to reach an energy
equilibrium, or "homeostasis", at which it felt naturally
comfortable. What was particularly interesting was that body weight
seemed somehow fixed, and was in most subjects resistant to change
over the short term. The prisoners with obesity in their backgrounds
were, it seemed, genetically inclined to reach homeostasis at a higher
weight than were others; the high-calorie diet only helped manifest
their genetic proclivity.''

Lictor also wrote about it once:

http://groups-beta.google.com/group/alt.support.diet/browse_frm/thread/4201b6160
703b9f2/7721581ca6647878?q=set+point+prisoners+group:alt.support.diet#7721581ca6
647878

It seems to be real.


http://www.obgyn.net/newsheadlines/womens_health-Endocrinology-20040726-23.asp

Studies of a stomach hormone called ghrelin in normal-weight women
indicate that the hormone may play a part in re-establishing a body
weight set-point after dieting and exercise.

http://www.foodproductdesign.com/archive/1995/0295CS.html

Other research by Duke's Schiffman points to one characteristic that
separates the overweight from their leaner counterparts: They want more
intense and varied taste


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstra
ct&list_uids=15005834

Experimental demonstration of human weight homeostasis: implications for
understanding obesity.

http://ajpregu.physiology.org/cgi/content/full/287/6/R1297

The drive to regain is mainly in the brain Levin Am J Physiol Regul
Integr Comp Physiol.2004; 287: 1297-1300.

...on the behavioral and metabolic responses during the development of
obesity, chronic food restriction, and relapse after ad libitum access
to food.... ...up to 16 weeks of restricted feeding ("weight-reduced")
followed by 8 additional weeks of refeeding ("relapsed-obese")....

Google leptin. You might start here:
http://arbl.cvmbs.colostate.edu/hbooks/pathphys/endocrine/bodyweight/leptin.html

Basically, leptin is secreted by adipose tissue (fat). When leptin
levels drop below a certain level, you get hungry.  Drop to far, you
get really hungry.
Here is the killer: leptin falls, when your fat cells begin to lose
too much of  their fat stores, so losing weight (adipose tissue
specifically) causes leptin to drop, and you get hungry all the
time--I think of this as that weird body hunger I get when my weight
get down to where I want it to be.
More bad news (ain't I a ray of sunshine so far) when someone is obese
for a long period, their body gets more fat cells (once the ones you
get full, the body has to create more to store the extra fat--bad
news, these do NOT go away when you lose weight :-(
More adipose tissue means that your body gets used to HIGHER leptin
levels (more secreting tissue don't you know), so when you lose weight
the leptin effect is even worse and wants you stay at the higher
weight (and remember you do not lose that damn extra adipose tissue).
What is the final story?
Don't know. Of course all of this is effect to a great degree by your
genes, and all this leptin stuff is pretty new, so very little is
truly known.

One side note: DO NOT BUY products claiming to have leptin replacement
for you. The stuff is hugely expensive to isolate (so likely anything
they sell is fake) and IIRC there is no evidence that oral replacement
had ANY effect.
Also again, it is not all gloom and doom, this is likely only one of a
couple thousand players that interact and regulate each other, so your
specific genes will cause so variability that any blanket statement is
not true.

The bottom line is, your body wants to be fat. For some, the call to
be fat is dramatic, for others their body might only whisper. For
those of us that have the call loud, the struggle is hard. BUT that
does not mean that we cannot overcome it! Fight the good fight, and
try to establish good habits (psychological can help offset
physiological). Don't give up, do not waver, and remember life is not
where you end up, but the journey to get there. You have your whole
life to get it right, so keep trying.

Dr. Dickie
Skepticult member in good standing #394-00596-438
Poking kooks with a pointy stick
====================================
"Let be be finale of seem.
The only emperor is the emperor of ice-cream"
Wallace Stevens-1923
=====================================

Well, once before when I lost some weight, I got down to 200 and just
stayed there forever.  This time I thought that would happen too --
some kind of major setpoint -- but it didn't at all.  The first time
around I wasn't counting calories, and I think my calorie level was
just basically at maintenance for 200 lbs., so I didn't lose any more.

I don't know whether I believe in setpoints or not.  In the course of
losing weight this time, I had a few stalls of 2-3 weeks, but nothing
major.  Perhaps sometimes people are confused, as I was, by simply
reaching a point where intake=output.  If you start out losing on x
calories a day and lose a fair bit of weight, you are likely to reach
a point where x is your maintenance level.  This isn't the same thing
as a setpoint; it just means you need to cut back on intake some if
you want to keep losing.

Chris
262/130s/130s
started dieting July 2002, maintaining since June 2004