Category: Obesity

Some of you know that I lost a bunch of weight after switching to a low-carb diet on January 1.

The latest news is this: my weight stopped trending downward at the end of April and has fluctuated around 143 for all of May, June, and July. Every time it dips below that I think, "Aha, I'm back on track." Every time it spikes above 144 (today, for example, it's 145) I think, "Uh-oh, here's the dreaded inevitable return of all the weight I lost." In general, though, I try to avoid over-extrapolating. This is a process of learning and experimentation.

I'm not looking for a miracle diet, nor claiming to have found one for myself, much less one that will work for everybody. Indeed, that word "miracle" irks me as it reminds me how much of our thinking about nutrition is, frankly, superstition. Understandably so, and I don't pretend to have some Spock-like immunity from magical thinking, but still. What I'm trying to do is reason more effectively about how I eat. It's sometimes hard — there's a lot of competing dogma out there — but I try to shake off my biases, or at least be aware of them, and be as rational as I can, even if that means more questions raised than answered. At some point I hope to post an update on how my reasoning has evolved; for now, this is just a status report.

To put the numbers in context: my weight on January 1 was 161 pounds. That may not sound like a lot for an adult male until you consider that I'm only 5'2" and I'm fine-boned, with small wrists and hands. You know that little guy Aziz Ansari? According to Google he is 4 inches taller than me, and he only weighs 136.

My average weight for the preceding 6 months was about 162.5, so in theory I could reasonably use that higher number as the "starting weight" for this diet experiment. Here's the raw data for the second half of 2015:

2015-07-01: 161.5
2015-08-01: 162
2015-09-01: 164.5
2015-10-01: 163
2015-11-01: 160
2015-12-01: 164

If I were to go back an additional 3 months the average would go even higher. But I decided not to use an average at all. For broad trends it feels simpler, and good enough, to just look at measured weight on the first of each month.

Depending on where I put the goalposts, I've been stuck for three months at something like 18-20 pounds below where I started. Let's call it 18 pounds — 161 minus 143. I am not unhappy about that. If you believe the "set point" theory (and I'm not saying I do), you could say I seem to have lowered my set point by 18 pounds with relatively little effort, and with an increase in satisfaction from the food I eat. I say "seem" because I've only been at this weight for 3 months, which is not a long time in the big picture of weight loss. Still, I'd rather be where I am than not, so yay for that.

On the other hand, I've still got a gut, and I think it's mostly from visceral fat (the kind that collects around the organs) rather than subcutaneous fat (which is just under the skin). The reason I think that is that when I tighten my abs there isn't much "pinch" in the skin above the muscle. There's a bit of pinchable flab, but most of my excess girth seems to be below the muscle. My understanding is that health-wise, visceral fat is worse to have than subcutaneous fat, and that it's also harder to get rid of. I'll keep this in mind in my ongoing efforts.

[UPDATE: I could have sworn I'd read that visceral fat is harder to lose than subcutaneous fat. I double-checked the other day and apparently it's the opposite. I was right though that visceral fat — the fat that accumulates around the organs — is worse health-wise than subcutaneous fat.

Hopefully I won't triple-check that at some point and find out I had that backwards too. If that happens I'll know the universe is messing with me.

Body fat isn't just "stuff" that sits on you passively like a schmear of cream cheese on a bagel; it's living, hormonally active tissue. If I understand correctly, visceral fat is the more dangerous type because it can wreak hormonal havoc on the organs it is in contact with. Something like that.]

I've been bugging friends in various forums about what I've been finding out about weight loss. One thing I am sure of: there is a huge amount to question, challenge, and reconsider when it comes to what we know about obesity and nutrition. We have so much to learn, and so much to unlearn, having discovered that what we already learned was bogus. Doing good studies on human subjects is very expensive, but so are the costs of health care for metabolic conditions. And confounding it all are people jockeying for political advantage of some kind, or looking to make a buck. There's always a buck to made in areas that are both deeply important to people and highly confusing.

I frequently feel overwhelmed, and I struggle with my intellectual limitations. For one thing, I want to get things right, but my biases are strong. And when I try to read about certain topics — recent ones are statistics and chemistry — the part of me that is "nerd" completely fails me. My eyes glaze over, and my brain folds its arms and says "You should have studied this stuff when I told you to 35 years ago."

For now I will keep trying to understand, and will keep spouting off and asking for correction and feedback. My attention span swings like a yoyo, but so far it seems to keep swinging back to this topic.

The NY Times article about the Biggest Loser contestants has been showing up in various places I follow. I've only skimmed it, but my preliminary reaction is "I'm surprised anyone's surprised." Which I know sounds dismissive, and I know it's annoying when people say that. But time and time again it's been shown that starvation diets don't work long-term.

It's old news that your metabolism slows down when you starve yourself. That's partly why simple calorie restriction doesn't work. That approach might be fine if calories-in and calories-out were independent variables, but they are not: reducing the former affects the latter. If you simply starve yourself using blind calorie counting, your body will change its energy budget, and now you're chasing a moving target, on top of which you feel crappy.

Another fallacy in "calories in, calories out" is that most people take that to mean calories in and out of the body as a whole. But what we care about is calories in and out of our FAT CELLS specifically, and that simple change in perspective leads to useful ways of reasoning.

We KNOW that WHAT you eat — as in protein vs. fat vs. carbohydrate — has a large effect on how your body meets its energy budget, in particular, how much energy it gets by burning fat. We KNOW that carbohydrates bump insulin, and insulin is the primary driver that tells fat cells to get fatter and more numerous. None of this comes from some recent magic discovery. It's old, boring, first-year-med-school news [1]. But I can't tell from the article how much of this knowledge was applied to the Biggest Loser contestants.

By the way, it also seems there is a lot of variation among individuals in how they respond to a given intervention, which to its credit the article does mention.

The findings about levels of leptin and other satiety hormones are interesting. My current understanding is that we still have a lot to learn about the hunger and satiety hormones, but they're a promising avenue of research. My understanding is that fat cells secrete leptin, which means it should be no surprise that huge decreases in fat caused the subjects' leptin levels to drop precipitously. I've seen a claim [2] that insulin blocks leptin from getting its message to the brain. But I hesitate to make any strong claims about hunger and satiety hormones — the research is much more recent than what we know about insulin.

My impression is that the Biggest Loser show took an approach to weight loss that has been proven to fail, and dialed it up to 11 for entertainment value. That's my impression, but I'm open to learning that I'm wrong. And if useful science can result regardless of that, then at least that's a good thing.

—

[1] At least that's what I've read. I'd be curious if any of you who are doctors or know doctors can confirm. One of the books I have shows a chart from a med school textbook that supposedly supports the "first-year med school" claim. I'll try to find it. But whether or not it's strictly true that any rookie med student "knows" this about insulin, I'm pretty sure it's long-established fact.

[2] The Skinny on Obesity (Ep. 3): Hunger and Hormones- A Vicious Cycle

My caveat on this video is that Lustig has been criticized for his claims about fructose. I'm not sure yet how to evaluate the criticisms. But what he says about insulin jibes with everything I've read. Again, I'm open to learning that I'm wrong.