Kevin Drum asks
Now, there are a bunch of things you might say about this right from the start. Maybe governments shouldn’t be in the business of running nanny state ads about personal nutrition. Maybe this particular ad was disgusting and shouldn’t have been released. Maybe obesity isn’t really that big a deal in the first place. But those weren’t the issues at stake. Rather, it was this single sentence in the ad:
Drinking 1 can of soda a day can make you 10 pounds fatter a year.
What, I thought, could be wrong with that? A can of sugared soda contains about 150 calories, and adding 150 calories a day to your diet would almost certainly produce a ten-pound weight gain over the course of a year or so. There are some caveats, of course:
So I’m curious: what do you all think of this? I’m open to argument here, but it seems crazy to me, less a politicization of science from the health commissioner than a case of geekdom run amok among the scientists. I mean, if you can’t tell people that adding a bunch of calories to your diet will make you gain weight, what can you tell them?
The problem is that the calorie balance interpertation implies a completely false understanding of what is going on. There is an extent to which geekdom can tolerate this level of nonsense and there is a point at which it must be combated.
I will compare to something I know Kevin gets. The calorie balance logic is equivalent to saying.
Government deficits drain savings. Savings are the engine of growth. Therefore, cutting the deficit immediately is our best shot at growth.
In both cases you are taking an accounting identity
- Private Savings – Public Borrowing = Net National Investment
- Calories-In – Calories-Out = Calories Contained in the Body
And, treating it as if it were a model of the world.
You have to be aware that public borrowing might effect private savings. In particular if public borrowing stimulates the economy it will increase private income which in turn will increase private savings.
You also need to be aware that Calories-In affects energy and hunger levels which not only feeds back to Calories-Out but also to other Calories-In.
I used to post this thing a lot, but since the blog has new readers it might be worth our while to look at how a properly functioning metabolism responds to a rapid increase in Calories-In
The big question we have is why does this stop working in some people? Just to note, there are many, many other feedback loops that are important as well. I point out this one because it so obvious both that it works in the healthy metabolism and that it fails in the unhealthy one.
You are probably aware of the relationship between diabetes and obesity. It is commonly assumed that obesity causes diabetes. This is in part because even some scientists are fixated on the accounting identity. However, there is a reasonable case that diabetes may cause obesity.
That is, the resistance of the muscles to insulin causes the breakdown in the “sugar rush” response (and other loops) which then breaks down the feedback from calories-in to calories-out.
Now, if it is in fact the case that sugary drinks induce insulin resistance this connection may still hold. However, it is almost certain that the simple minded thinking that in general dropping a 150 calorie item from your diet will not feedback on other metabolic components promotes a fundamental misunderstanding of what’s going on.
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For the geeks. Yes, in truth even what I have written here is a gross oversimplification and ignores central facts such that an increase in obesity from sugar consumption must be proximately caused by an increase lipogenesis or a decrease in lypolysis both of which are hormonly regulated processess. That is, just as there is no such thing as immaculate transfer there is no such thing as immaculate obesity.
You can’t just throw organic matter at a metabolism and get fat. You actually have to create fatty acids and bind them up into triglycerides. Any model that assumes that you can is going to wind up disappointing you and of course there are a fair bit of disappointed dieters. We need to do better as intellectuals.
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Friday ~ October 29th, 2010 at 2:21 pm
John M
I agree. Soda is good for you. Also, the phrase “all things being equal” is meaningless.
I like my truth as a unified field.
Friday ~ October 29th, 2010 at 2:28 pm
Frank Schmitt
I’m trying to hone a new “elevator pitch” for what you’re discussing here, and I’m curious whether this captures it:
“Trying to weigh less by eating less and exercising more is like trying to sleep less by staying up later and getting up earlier. You can keep it up for a while but sooner or later you’re either going to have a “failure of willpower” or end up in the hospital.
“You can’t brute-force your metabolism any more than you can brute-force your sleep cycle. You have to fix the underlying issues, if any, that are keeping you fatter than you’d like. ”
Of course what the “underlying issues” are and how to fix them is still a matter of some debate (I’m a disciple of Taubes on this, FWIW).
Friday ~ October 29th, 2010 at 3:13 pm
DJAnyReason
That is an interesting idea. Of course, my own personal experience over the last year, in which I ate less, exercised more, and lost >30 pounds suggests differently.
Wednesday ~ November 17th, 2010 at 10:08 am
Simon
I didn’t cut down eating at all. In fact I didn’t even intend to lose weight. Just a proper dinner every day, a lower intake of sweets, and that 20 min walk to the bus stop every morning and in the course of 2 weeks I lost approximately 11 pounds. If you do it right it’s actually easy. I just wished that I’d had kept this routine going.
Friday ~ October 29th, 2010 at 3:13 pm
Wonks Anonymous
Oddly enough, both Casey Mulligan and the Post-Keynesians/Chartalists agree that public spending can increase private savings.
Friday ~ October 29th, 2010 at 4:23 pm
jazzbumpa
Karl -
Your reasoning would be more valid for someone existing close to a sensible energy balance.
I don’t think you’ve taken into consideration that the 150 cal from the soda exist in a matrix that is 1) otherwise nutritionally useless, and 2) likely in addition to an already excessively super-sized calorie count.
Since those 150 cal are in excess of what the body needs, they will either be eliminated or stored. Take a trip to WallMart and you’ll see plenty of evidence of storage.
In this context, the vid of the skinny kid is more misleading than useful, since a pre-schooler’s metabolism is pretty significantly different from that of the parents, who are highly unlikely to do laps around the fireplace in any event. I’ll place money on them falling asleep in front of the TV.
Sure, there is an obesity-diabetes loop, and insulin is key to understanding it. But dropping an unneeded 150 nutritionally empty cal from anyone rotating in that loop is going to be directionally correct, irrespective of second and third order complexities.
Cheers!
JzB
Monday ~ November 1st, 2010 at 10:50 am
Corey Mutter
The “Hacker’s Diet” gets around these limitations by combining calorie restrictions (in the form of good old-fashioned calorie counting) with a feedback loop to account for metabolism.
In the HD case, it’s weighing in daily, and taking a moving average to account for weight changes due to water, etc. One adjusts one’s calorie-count target as necessary to maintain the target weight loss rate as measured by said moving average.
It has a leveling-up exercise component which I completely ignored, and still lost 50 pounds in a bit over a year.
Of course I gained it all back after stopping the counting of calories, so there’s that.
Tuesday ~ January 3rd, 2012 at 9:47 pm
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