Do other theories on obesity dispel Calorie Balance?
A little while back I listened to this interview with Stephan Guyenet from Whole Health Source blog did with Chris Kresser of The Healthy Skeptic. I highly recommend listening to this, there's lots of info there. Stephan discussed various theories on obesity such as Omega 6's, gut flora, inflammation/immune disorders, etc.
Without trying to put words in Stephan's mouth, my overarching take-away message was that Stephan believes that our bodies have "set points" managed by an "adipostat" located in the hypothalamus. The major hormone involved with the adipostat is leptin. Leptin is secreted by fat cells and circulating levels are associated with one's level of fat mass. The theory is that something throws off the adipostat, and that something leads to leptin resistance of the hypothalamus. When leptin's "stop eating" signal fails to reach the brain, we overeat. Basically each of the possible causes of the obesity epidemic triggers leptin resistance triggers overeating.
OK, so Americans are eating more (150-300 cal/day on average) and getting fatter. Sounds like Calorie Balance theory to me! Gary Taubes in his NYT article stated as much as well, but then went on to write his tome to explain why evidence of Americans eating more was not supportive of Calorie Balance. I guess the mystery is why we overeat and not that we do.
I kind of like Stephan's set point theory -- it makes a lot of sense to me. But it doesn't really counter Calorie Balance, instead he offers explanations as to why we "override" our energy balance. I have to disagree that ELMM is ineffective for weight loss. That is simply not true. It works every time it is tried. Perhaps he means "ineffective" because of difficulties implementing it. But telling people just to cut carbs is no more effective. Despite claims in the New Atkins, I've yet to see any study demonstrating greater success rates and maintenance rates with LC. Yes, there are success stories out there (and I consider myself to be one), but there's no dirth of LC'ers who have regained some or all of their weight back (and I was one of those, twice). To his credit, Stephan notes that LC spontaneously causes most of us to eat less.
As for the calories out, I think Stephan, like Taubes, has gotten sucked into this notion that all exercise does is make you hungry and that everyone who exercises is stopping off for an ice cream smoothie on the way home. Yes, there's some truth to that, but not for everyone. Just because an hour of cardio doesn't offset that smoothie, it's better to have expended those calories than to just have the smoothie. I don't think it is a bad strategy at all to promote exercise of all sorts to at least prevent obesity. While burning 100 or 200 calories may not seem like all that much it does compensate for the fact that on the whole, we expend less energy in our daily lives. Just think remote control, power windows, no microwave, even featherweight vacuums. Also this study demonstrated that moderate exercise increased fat loss independent of dietary composition and did so because the exercisers essentially didn't slow down as much the rest of the day. The added fat loss was attributed to maintaining total daily energy expenditure because the calories actually expended for the exercise itself was compensated for with caloric intake. He does mention a study showing cycling sprints to be more effective for weight loss. Intuitively this sprint vs. long slow cardio seems to counter the Calorie Balance, but as I recall this type of training actually increases energy expenditure for a period following the exercise itself. (I would add that we get less ATP out of glucose under anaerobic conditions so this would also reduce the "in"). Both of these support exercise to increase the "out" side of the equation. Exercising to lose weight is not ineffective if one doesn't ignore the concurrent advice to eat less (or at least not eat more).
None of the obesity epidemic theories dispel the Calorie Balance. Some go to explaining why some may overeat and/or become less active to get the ball rolling towards obesity, but it is physically impossible to accumulate fat mass w/o taking in more energy than is expended. And I'm skeptical that these theories explain why we overate so much in the first place, as much as they may explain why we continue to overeat even after becoming considerably overfat. Many of the proposed culprits (fructose, white wheat flour, veggie oils) have been around in relative abundance since before this epidemic started and they didn't prompt overeating then.
Without trying to put words in Stephan's mouth, my overarching take-away message was that Stephan believes that our bodies have "set points" managed by an "adipostat" located in the hypothalamus. The major hormone involved with the adipostat is leptin. Leptin is secreted by fat cells and circulating levels are associated with one's level of fat mass. The theory is that something throws off the adipostat, and that something leads to leptin resistance of the hypothalamus. When leptin's "stop eating" signal fails to reach the brain, we overeat. Basically each of the possible causes of the obesity epidemic triggers leptin resistance triggers overeating.
OK, so Americans are eating more (150-300 cal/day on average) and getting fatter. Sounds like Calorie Balance theory to me! Gary Taubes in his NYT article stated as much as well, but then went on to write his tome to explain why evidence of Americans eating more was not supportive of Calorie Balance. I guess the mystery is why we overeat and not that we do.
I kind of like Stephan's set point theory -- it makes a lot of sense to me. But it doesn't really counter Calorie Balance, instead he offers explanations as to why we "override" our energy balance. I have to disagree that ELMM is ineffective for weight loss. That is simply not true. It works every time it is tried. Perhaps he means "ineffective" because of difficulties implementing it. But telling people just to cut carbs is no more effective. Despite claims in the New Atkins, I've yet to see any study demonstrating greater success rates and maintenance rates with LC. Yes, there are success stories out there (and I consider myself to be one), but there's no dirth of LC'ers who have regained some or all of their weight back (and I was one of those, twice). To his credit, Stephan notes that LC spontaneously causes most of us to eat less.
As for the calories out, I think Stephan, like Taubes, has gotten sucked into this notion that all exercise does is make you hungry and that everyone who exercises is stopping off for an ice cream smoothie on the way home. Yes, there's some truth to that, but not for everyone. Just because an hour of cardio doesn't offset that smoothie, it's better to have expended those calories than to just have the smoothie. I don't think it is a bad strategy at all to promote exercise of all sorts to at least prevent obesity. While burning 100 or 200 calories may not seem like all that much it does compensate for the fact that on the whole, we expend less energy in our daily lives. Just think remote control, power windows, no microwave, even featherweight vacuums. Also this study demonstrated that moderate exercise increased fat loss independent of dietary composition and did so because the exercisers essentially didn't slow down as much the rest of the day. The added fat loss was attributed to maintaining total daily energy expenditure because the calories actually expended for the exercise itself was compensated for with caloric intake. He does mention a study showing cycling sprints to be more effective for weight loss. Intuitively this sprint vs. long slow cardio seems to counter the Calorie Balance, but as I recall this type of training actually increases energy expenditure for a period following the exercise itself. (I would add that we get less ATP out of glucose under anaerobic conditions so this would also reduce the "in"). Both of these support exercise to increase the "out" side of the equation. Exercising to lose weight is not ineffective if one doesn't ignore the concurrent advice to eat less (or at least not eat more).
None of the obesity epidemic theories dispel the Calorie Balance. Some go to explaining why some may overeat and/or become less active to get the ball rolling towards obesity, but it is physically impossible to accumulate fat mass w/o taking in more energy than is expended. And I'm skeptical that these theories explain why we overate so much in the first place, as much as they may explain why we continue to overeat even after becoming considerably overfat. Many of the proposed culprits (fructose, white wheat flour, veggie oils) have been around in relative abundance since before this epidemic started and they didn't prompt overeating then.
Comments
"...but it is physically impossible to accumulate fat mass w/o taking in more energy than is expended."
The question is why do some people keep taking in more energy. You cannot claim that all obese people eat too much total food because they are gluttons, weak-willed and lazy.
Obesity is a disorder of excessive fat accumulation.
Giants are not tall because they eat a lot of food. And many do eat a lot of food. But it is not necessary to eat a lot to reach their height. They have a hormonal disorder that causes their tissues to grow at an abnormal rate. They "accumulate" height.
Obese people accumulate fat. And many obese people eat a lot. Some don't. But when they do eat a lot it is because they are accumulating fat. They are starving at the cellular level.
You contradict yourself because in this statement you acknowledge that obesity is the result of people taking in too much energy!
I didn't say the obese are gluttons. For one, it is quite easy to "passively overeat" energy dense foods which I'm sure many do. Also our bodies do not seem to sense liquid calories very well.
My point in this post, however, was that many supposedly "competing" explanations for obesity ultimately boil down to Calorie Balance.
What fraction of the population that try to do it, say over say 10 years, permanently change their basic psychological traits? (change forced from outside is a separate issue)
What fraction who try to do it, permanently change, say over 10 years, their social situation? Financial? (again separate a deliberate self-initiated attempt from forcible change, like financial collapse)
Almost none.
The the whole "dieting is ineffective" stance ...
Compared to what?
I make these comparisons because IMHO one of the major causes of obesity is lack of attention and awareness. The human organism has a tendency to put things that are not an immediate threat on auto pilot. This includes eating.
There's no reason to make an insult out of it - everyone does it to some extent.
Seems to me dieting is no worse or better than any other attempted personal change, complete with new bestsellers every couple of years saying all the previous theories were wrong - the proof they're wrong is that not many people changed.
This explains why the males, especially, in primitive hunter-gatherers were very lean. Extra weight is a huge burden when you are running long-distances (chasing after wounded game) or climbing trees to get fruit and coconuts or any other activity that requires moving the body around. Even the women were active. Trying bending over for several hours (in order to hoe the garden) while fat versus bending over while lean.
Feedback from the muscles is the missing component of the set-point theory. Leptin is enough to stop massive overeating, but not overeating by 100 kcal/day, and 100 kcal/day is enough to cause 10 pounds/year or 100 pounds/decade of weight gain. What stops the 10 pound weight gain is muscular feedback.
You can take advantage of this muscular feedback by incorporating exercises where excess body fat is a tremendous liability. For example: pullups, gymnastics in general, long-distance running, rock-climbing, yoga twists and forward bends where a big stomach gets in the way, yoga handstands or other hand balances where excess weight is extremely hard on the wrists. Sprinting gives feedback ONLY if you time yourself and strive for good time. A fat person who sprints slowly and is content with their slow times gets no feedback. Swimming provides negative feedback, since body fat helps keep a swimmer afloat. Olymipic class swimmers like Phelps (eating 12000kcal/day and staying lean) are NOT counter-examples.
My own exercise routine has always been yoga (including handstands) plus pullups. As soon as I gain a few pounds (such as after Thanksgiving with the relatives force-feeding me junk), I feel that my morning exercises become more difficult, and so I cut back for a days.
I have accidentally stumbled into what was messing with my dietary feedback control of my weight, used it to lose 20 pounds, keep it off the last three years, and control my weight +/- 0.6 pounds of the natural regulated set point my body found with my dietary changes.
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