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He wraps up a lot of obvious points in a lot of science that he doesn't understand.

That's odd. You would have thought that an undergraduate physics degree (even from a liberal arts institution) and a masters in engineering (OK, that one's from a real school) would have given him at least a basic grasp of the issues. :)

His "20 calories a day" explanation is not the argument he is making. Rather, he's pointing out that it's absurd to think that the sole difference between an obese 70 year and his svelte wife is the one sugar cube per day the fat one added to his morning coffee. Are you arguing that it is indeed this simple, and that all we have to do to have a thin and fit population is to drink black coffee?

p.s. Why the new account?

It's rather more likely that we need a population who accepts that their weight fluctuates up naturally, and is willing to put in the extra effort to make it fluctuate back down by deliberate effort.

Taubes is portraying it as a sugar cube every day. Instead, it could be cookies, brownies and egg nog over Christmas, followed by a normal diet for many weeks. It could also be eating a diet acceptable for a 20 year old when you are 40.

Taubes is portraying overeating as mu=20, sigma=0. That's a fallacy.

What's more important, the two pieces of paper he received or the fact that his own arguments clearly depict he doesn't understand? He says:

" Does anyone – even Jonah Lehrer or the neuroscientists he consults – think that the brain, perhaps in cohort with the gut, is making decisions about how much we should eat, on how long we stay hungry and when we get full, so that we don’t overshoot by 20 calories a day. That’s matching intake to expenditure with an accuracy of better than 1 percent. (We consume, on average, about 2700 calories a day, so matching energy in to energy out and not overshooting by 20 calories requires better than one percent accuracy.)"

"...we actually have to be perfect in our matching of intake to expenditure or we’re going to get inexorably fatter (or leaner, if we err on the side of going hungry), or at least we have to average perfection over decades."

His argument is that the body is not accurate to within 20 calories a day. He appears unaware of the fact that this kind of regulation, which I agree isn't possible on a day-to-day basis (the brain never says "don't eat that last 1/12 of a candy bar"), is unremarkable when amortized over time. That is where his scientific inexperience shows. "Averaging perfection over decades" happens all the time and is perfectly unremarkable. He is oblivious to this fact.

This is a fatal error. Regardless of how it fits into his larger argument, he gets this basic and fundamental point wrong. When an author can't get facts like these straight, I become suspicious of the rest of his arguments. And indeed, a random sampling shows they are fundamentally broken. I would not trust him to explain any kind of complex science.

When an author can't get facts like these straight, I become suspicious of the rest of his arguments.

I agree that this is a pretty good standard to adhere to, but there are other explanations: perhaps Taubes understands the issues well, but didn't do a great job of translating them to analogies. Or perhaps you (as reader) are not correct in your understanding of his argument. I suspect Taubes would agree with you that given an appropriate long-term feedback method that fine regulation is possible, thus I presume the actual issue is something else.

I'm inclined to trust Taubes because I've enjoyed some of his prior writings. Here's an award winning article of his that was published in Science: http://www.junkscience.com/news3/taubes.html. You might enjoy this earlier article as an example of his style applied to a different topic. While it's certainly possible he's completely wrong here, I don't think it's because he lacks any fundamental understanding of science.

As I read it, Taubes' basic critique is that the 'calories equals weight gain' formula is so flawed as to be almost useless. The more I look into it, the more I agree with him. Yes, obviously at the extremes there are physical limits involved, but presuming a purely linear response just seems silly. I cheer him on in his attempts to come up with something better.

... stating that weight gain is due to eating more calories than you burn is neither tautological, vacuous, nor inane. It might not be satisfying to the author, but it is a cogent and useful explanation of why people gain weight.

No, it's not useful. What defines "calories absorbed" and how is that related to the actual amount of food ingested? Do all possible calories in a given bite to eat always factor in the theromdynamic equilibrium or do some of them just pass through your system? What about "calories burned"? What proportion of calories burned in a day are due to walking, exercising, thinking, or just sitting there. How much does your metabolism fluctuate, and what controls it?

It's true that if you are overweight, then you absorbed more calories than you burned, but the converse doesn't necessarily give insight into what to do? You could eat less, but then maybe the body would be more efficient about extracting calories from the food passing through, or maybe it would lower your standing metabolism so as to not burn as many calories during the day.

I have maintained a healthy weight for some time, while my food and activity level has fluctuated wildly. Clearly, my body is doing some pretty fancy stuff "behind the scenes" to maintain energy balance, and that seems like the most important factor in weight gain or lack thereof.

Lastly, I will say your post brought up an interesting thing: you mention the law of large numbers. I believe this indicates you think there's a target caloric intake, and each day our body draws a random variable of calories, with the thermodynamic equilibrium as the expected value. It's an interesting model, but I'm not sure if that's realistic. I feel like what I eat in a given day is determined more exogenously than endogenously (e.g.: who I visit, what they want to do, what restaurant I walk by, what the special of the day is, etc). It's an interesting idea, though.

Why do people get fat?

> Secondly, stating that weight gain is due to eating more calories than you burn is neither tautological, vacuous, nor inane. It might not be satisfying to the author, but it is a cogent and useful explanation of why people gain weight.

It's an excellent starting point, but it might not be that useful by itself unless you like working against your body's self-regulation mechanisms.