Formspring round 1
My first two questions! Keep ’em coming.
Okay. What the heck is formspring? Why not just open your blog to questioners? (Not trying to sound cranky, just confused.) Signed, Merry the Luddite
Um because hello? NEW AND SHINY. It may turn out that this goes the way of my twitter account (abandoned.) I do think that this lets people feel more anonymous than asking questions on blogs because there’s always the fear that the blogger in questions has ways of knowing exactly who is asking what.
Hey Attrice! Longtime reader, first time formspring interrogator. My question is: What experience and/or research study changed your mind about the idea of a fixed setpoint? Danke!
Oh wow, good question. Now I could post something super duper long and rambly or I could give a pithy anecdote and then link to and quote others liberally. My natural inclination is to do the first, but I’ll spare you.
First I should start off by saying that my mind wasn’t changed about set point so much as tweaked. Hopefully, I’ll be able to give you a better idea of what I mean with my little anecdote below.
So, some of the first strong evidence for a weight set point was in research done on rats. Basically, you allow rats access to rat food and they tend to maintain their weight in a pretty tight range. You take away the rat food (poor rats!) and they lose weight, their metabolisms slow down, they move less and, once food is reintroduced, quickly eat back up to their previous weight. Simple.
However when researchers expose rats to what is actually called a ‘cafeteria diet’ (lots of options, many of which are particular scrumptious to our rodent friends) the rats quickly gain weight above their ratty set point. Put them back on rat chow and they lose this weight and once again maintain at their original weight. So being surrounded by highly palatable food enables the rats to overcome their normal set point.
Now don’t read too much into this. I’m not saying that people would be better off with our own version of rat chow. More that the homeostatic control of weight definitely exists, but which weight it maintains has a lot to do with environment – what kind of food options we have, how much movement is necessary in our daily lives. This is why I’ve said before that more than even a ‘lifestyle change’ I envision my personal weight loss as an environmental change. I can’t actually change my environment, of course, but I find it a better fit mentally in terms of what I’m doing.
Now here’s the point where I have to acknowledge that whether or not people can lower their set point once it has been raised is far from decided in terms of research. The generally accepted opinion, afaik, is that it’s much easier to gain weight and raise one’s set point than the reverse. Linda Bacon even says this is her HAES book. The just-so story for this is that until recently humans didn’t really ever worry about getting too much food on a regular basis so the weight control system is asymmetrical in that it defends weight loss more than weight gain.
However, research is all over the place on this one. We know that metabolism slows during dieting – which would support the above view. We also have research which shows this effect disappearing once people have lost weight and are put on maintenance calories for their new weight. That would suggest that it’s this deficit that affects metabolism and not the weight one ends up at.* So if this is true (and it may not be) then that argues against overall metabolism being behind weight regain, but that doesn’t mean other systems might not be behind it.
Ok, last thing, some researchers are now using the term settling point or settling zone to talk about this tendency of the body to maintain weight in a particular range. This differs from set point though in that it’s the zone the body settles in while in a particular environment and not a pre-programmed weight that the body ‘wants’ to reach. Basically the view is the body will settle at a particular weight when the large variety of factors that influence weight reach equilibirum. Which sounds circular I know, but when I post this on my blog, I’ll post some links that are a little more eloquent than I am.
Ok, just a few links:
Article on study done on RMR in women post weight loss (unfortunately I can’t access the actual study.)
Pdf of a lecture where some of the set point v settling point stuff is discussed
Lyle Mcdonald’s articles on bodyweight regulation. Very good reads.
Ok I’m trying to avoid doing a lot of ‘here’s a study that “proves” my point’ type links because I’ve decided that the literature is too vast and that’s not the way science works anyway. So I’ve purposely tried to keep the links more general than that. But for anyone interested I believe googling “Pinel” and some version of set point will give you hours of fun time reading. Also the researcher referenced in the first link has done a lot of work on obesity and metabolism. Have fun.
* I should also add that if this is true, then it’s probably only true when we’re not talking about unhealthily low levels of body fat. Bringing someone down to the lowest possible levels of body fat will cause some crazy ass stuff to go down (scientifically speaking.)