On the Margin
If I could sum up the two most useful things I learned in business school that have developed further since I’ve been out, it’s that (1) almost all good decision-making is done on the margin, and (2) almost any form of risk reduction really just boils down to some form of insurance. Business school augmented by Trading Places adds a third: (3) any sufficiently interesting form of investment finance has a direct analogue in gambling.
Good dietary management, I’ve found, also occurs on the margin. What has worked for me so far is what I might consider a “naive thermodynamic philosophy,” in which you essentially atomize your efforts into daily, standalone units and view your progress as an energy balance equation as follows:
Base Load + Exertion + Surplus/Deficit = Meal Intake + Extra Intake
Surplus/Deficit is the measure of imbalance between intake and output. My basic budget is that you gain a pound for every 2,500 kcal (food calories) of accumulated surplus, and you lose a pound for every 3,000 kcal of accumulated deficit. The precise truth is about in the middle of those two, but building in a spread makes sure you’re never surprised by the results of your actions.
Most fad diets and diet pills spend a lot of time convincing you that your Base Load energy (also referred to as Resting Energy Expenditure or various terms to that effect) is a controllable quantity, a tidy function of manipulable variables. Certainly, there is data that eating a hearty breakfast “jump starts” your metabolism for the day, or that doing your exercise (Exertion energy) earlier in the day can also raise your Base Load if you don’t try to go to sleep right after, etc.
I feel like a lot of this stuff is pretty hokey for practical purposes, though, and is at least a distraction from the truly manageable parts of the energy balance: principally intake, followed by exercise.
I read through a published study of anorexic women who went from essentially near-starvation to tube feeding. In the course of the first eight days of hospitalized tube feeding, their base caloric need went up by about 12% after controlling for increased body weight over that time. For them, that was around 125 kcal per day, which for somebody my size would translate into something around 300 kcal per day. Over that same eight day time period, the average body temperature of the test subjects increased by about 1 F, a clear indicator of metabolism almost literally firing up in these previously near-death girls. After more than two months of forced nutrition, they essentially had just over another 125 kcal per day increase in base load, again controlling for their significant weight gain over that time.
If you look at this extreme case where you went from a body in near-shutdown to a rapid weight gain scenario, that theoretical equivalent 300 kcal/d adjustment for somebody my size would only be worth a pound of fat over an 8-10 day period. Nothing to sneeze at, but a focused effort at dieting should probably result in a daily deficit of as much as 1,000 kcal, netting you two pounds lost per week with a weekly cheat day where you take in your Base Load with no deficit.
What I’m saying is not that optimizing your Base Load is a bad idea, but that intake is infinitely more predictable and generally easier to control, with a bigger potential impact to boot. Putting the focus on Base Load ends up pushing you into pseudoscience hand-waving (“Caffeine helps because it raises heart rate! No it doesn’t! But it suppresses appetite! But it’s a diuretic! That doesn’t matter! Yes it does!”) or apathy (“I could exercise, but it’s late in the day so why bother.”) or balloon squeezing (“I’ll force myself to eat breakfast even though I’m not hungry since that’s healthier.“).
The anti-gluten people, who must be tied in with the breastfeeding mafia, have entered the dietary arena, claiming some business with insulin can wreck your resting metabolic rate or what-have-you. I’m just wondering from a thermodynamic perspective where all that phantom energy need is going (or not going) if your preferences in wheat products are so impacting your body’s most essential activities? The starving girls had noticeably lower body temperature and probably failing organs in some cases, and their corrected-for-weight caloric need only jumped by 25% from near-death to recovery.
To jump back to the alleged theme of this post, I feel that Base Load manipulation is a gaming the average, where dieting and exercise are managing the margin. But the margin is really where you gain or lose weight: that surplus or deficit, however achieved, is changing your body every day. Before you worry too much about the efficiency of the conversion, it’s best to think about the controllable inputs and outputs.