Nov. 10th, 2011

haggholm: (Default)

Since I decided, with Jaimie’s help, to try to get on a healthier diet, prompted by my recent decision to try BJJ competition but a good idea anyway for obvious reasons, I’ve spent some time reading about healthy diets, rather more time listening to Jaimie talk about it (as she’s done a lot more reading than I have energy for), and some time pondering it. This post isn’t likely to contain any great revelations, but is meant more as a way to organise my own thoughts (correct or not). It may well be that I am making glaring omissions because I’m not that well-read on the subject, but I can’t very well figure out what I need to read up on until I sort out my own thoughts in advance.

Let me hasten to assure you, by the way, that I am not planning to obsess unhealthily over this until I can play my rippling washboard abs like a xylophone, nor to start morally judge people over their adiposity. Still it happens to be true that the reason for my own personal lovehandles is less genetics than a long lack of interest in healthy food, and whatever the fat positive crowd may say (and I morally agree with them), I just can’t put any stock in claims that overweight is without health consequences.


The world is full of preposterous fad diets (Gerson, Ornish, cabbage soup, morning banana), but there are a number of prima facie reasonable, but contradictory diet ideas out there as well. Diets that have any shred of evidence for effectiveness in healthy weight control seem to focus on reducing either fat intake, or carbohydrate intake, or total energy intake by controlling both. Pick any basic type of diet—low carb, low fat, low calorie, vegan, paleolothic, macrobiotic, you name it—and unless it’s a bonkers variety like cabbage soup, you will no doubt easily dig up a mountain of evidence in its favour, making much reference to the dangers of trans, saturated, or polyunsaterated fats; the benefits of ketosis (sustained or periodic); glycemic indices; and any number of biochemical processes.

Faced with any such evidence load, I must admit myself defeated: I’m not a biochemist, and I don’t understand it. I might be able to read up enough to recite the party line, but I wouldn’t get it. I don’t even know the Krebs cycle, for heaven’s sake! I can at best follow and roughly understand what you’re saying, but I’d need at least another university degree to be in a position to spot any errors. And when one source claims that fat is the root of all evil, and another would stick that label on carbohydrates, or some fats but not others, or what have you, what is a poor non-biochem-postgraduate to do?

Personally, I suspect that lots of these diets work, but I’ve yet to see anything that convinces me that the specific rationale advanced for any one of them is really to credit. A funny thing that emerges when you follow any paleolithic, low-carb, low-fat, or energy-restricted diet on the market is that you tend to end up consuming less energy—in effect, it seems that all of them contain “reduced calories” as one component. One immediately turns to ask whether there’s any more to it. In some cases it seems fairly probable that it isn’t so. For instance, a 2002 Cochrane review compared a low-fat and a general low-calorie diet and found them to be equivalent. I think if you lined them all up, they’d all agree on some basics:

  • Eat a reasonable amount of food and a reasonable amount of energy (calories). It might not say this up front, but do the food-math. I think that low-fat, low-carb, and low-calorie diets in name are all low-calorie diets in fact.
  • Don’t eat so much heavily processed stuff full of refined sugars and ground-down food products.
  • Keep track of what you eat. I’ve seen some pretty convincing research establishing that people who keep track of what they eat tend to eat less and eat more healthily even if they don’t otherwise have much of a plan. Presumably this is a kind of Hawthorne effect.

And of course if you go on a diet, or several diets, consciously trying to lose weight or BFP or feel more energy or what have you, then if at least you succeed, you will naturally tend to attribute your success to what you were doing at the time (confusing correlation with causation; damned hard to avoid with a sample size of one!). Maybe it was because of diet X that you finally got in shape, but maybe diet Y would have worked just as well, even though it failed last time, because this time you’re more determined, your metabolism has changed, your lifestyle has altered, you just have less of an appetite these days, you follow diet plans more strictly… The possibilities are nigh endless, and this is why no one can really know that a particular diet is what works for them. (You can fairly say that “diet X works for me” if you’re on it and get healthier, but you just can’t know that diet Y wouldn’t have worked in its place.)

What of all the rationales, then, all the reasoned and detailed arguments about where polyunsaturated fats go to die and how glycemic indices change depending on whether you eat 26 grams of carbohydrates a day or only 22.5 grams? —Well, what of them? It’s very often true of basic medical research that translating from chemical or cellular scales to gross physiological ones is difficult. The human body is a system of some ten trillion human cells living in community with some hundred trillion bacteria; it’s not a scaled up test-tube! Lots of things can be demonstrated admirably on a cellular level but fail entirely to happen in the human body because it will synthesise, regular, deposit, or excrete things you attempt to add or withhold, use alternate pathways, and what have you.

To take a concrete example, when faced with the evidence linking glycemic index to insulin responses and fat deposits I can only nod and agree that as far as I can tell, it makes sense; but at the same time I know that I’m not actually qualified to tell whether it does. The one question I feel qualified to ask is whether or not this line of evidence has, or has not, put the cart before the horse. Before investigating how carb restriction is a superior method of healthy weight loss to fat restriction, we must establish whether it is. Curiously this seems to be discussed more rarely (though as I said, my reading has been pretty cursory yet). If it turns out that a low-carb diet is superior to an energy-equivalent low-fat diet, then and only then are the mechanisms important to study.

I’m not dismissing basic research here, by the way, or siding with people who misguidedly sneer at research less than Phase III trials. Discovering basic chemical mechanisms in vitro is a perfectly good way to arrive at a hypothesis to test in vivo. Just make sure that once your hypothesis is generated, it’s tested before it’s refined and elaborated. (I don’t mind if you obtain a cart before you obtain a horse, in other words, so long as you hitch them up in the proper order before you try to take me for a ride.) Nor does approaching a problem from that direction mean that the conclusion is wrong. It just means that I need to see the in vivo study before the in vitro study is of the faintest interest to me as a consumer; properly the in vitro stuff should be of real interest chiefly to other researchers—because, to reiterate, the in vivo effects of in vitro findings are difficult and error prone even for experts to predict, and as I am not an expert, it’s pretty hopeless.


My own personal suspicion is that much of the differentiation here is basically product differentiation: If (as I suspect) a large array of diets all work, then the way to launch a successful new product in the diet marketplace is to come up with a variation that sticks within what works but is sufficiently distinct to be marketable on its own, and provide rationalisations for why this particular thing is so superior. I use the language of economics here, but it might not be money per se. Maybe the people selling a diet are indeed selling literal products, but they could also be selling books, or social capital as valued members of an online community. And their product really does work, after all…

With my very tentative working assumption that this whole array of non-insane diets all work and that the differences are far less important than the similarities, my equally tentative conclusion is that the most important feature of a calorie-restricted diet is the psychological factor: How easy is it to stick with? Here, I suspect that the low-carb diets have an edge over low-fat diets simply due to relative satiety. You can eat yourself unhealthy by eating too much sugar and starch, and you can eat yourself unhealthy by eating too much fat; but it’s easier to do it on the former because the latter make you feel fuller.

In other words, my current stance is: Look at all the mainstream healthy diets. Pick the one you think will be easiest to stick to. Stick to it. It’ll probably be good for you if you do. And you might still not lose weight, because (1) it can be very difficult to stick to restricted diets and (2) some people are genetically predisposed to carry more fat (but going on that healthy diet is a good idea anyway, as long as you don’t mistake starvation for health).


Further reading I should do:

  • Are there horse-before-cart studies comparing low fat, low carb, Atkins, paleo, &c. diets? I.e. studies that attempt to perform longitudinal comparisons at controlled calorie consumption levels?
  • …I was going to make a list, but the above item really looks like the necessary first step.
haggholm: (Default)

I’m feeling oddly adrift in my Linux taste, these days. I wasn’t a Linux evangelist before, mind, but I would like to be able to answer with a recommendation if somebody asked me what distribution I think they should run. For a long time I would have confidently replied Ubuntu!, but right now I should be unable to do so unless their æsthetic sense differed radically from mine, for starters. I started this year an Ubuntu user. Right now I’m a slightly disgruntled Fedora user in search of something better.


Ubuntu

My experience with Ubuntu started bright and turned better with the years. It was always intended to be easy, friendly, and ready out of the box. There was a time when I was too attached to the tweaking of my Gentoo days to appreciate it, but once I started worrying about two or three computers rather than just one desktop, Gentoo felt like too much work, and Ubuntu’s satisfactory out-of-the-box experience was a relief. Installing it is a snap: Always works, never causes trouble. Upgrades are smooth. Release updates were a bit of a jar from the rolling schedule of Gentoo, but they always went without a hitch, or at most very minor hitches. (Except when I chose to upgrade to beta versions, but if I choose a beta version I know I’m inviting potential trouble!)

The problem is that while Ubuntu has an exquisitely engineered distribution, what it actually distributes is less satisfying to me of late. In part I get annoyed by the tension between Ubuntu and the FOSS community—all the controversies over contributor agreements, playing poorly with upstream, demanding that other projects adhere to their schedules, and apparently picking their software stack based on political desire for control:

Since both init and Xorg are flexible enough to provide the sorts of improvements that Shuttleworth advocates, the suspicion is that such decisions are not technical, so much as political. That is, what concerns Ubuntu/ Canonical is not the technical merits of the applications, but its ability to dominate the projects that dominate its software stack.

The launch of Ubuntu One sort of cemented my generally suspicious attitude toward Canonical. Still, while I might not be wholeheartedly enthused by the company, the product still seemed good.

Until they launched Unity with no good fallback or alternative and in a fit of anger and disgust I left Ubuntu behind. People can claim all they like that it’s similar to GNOME 3. To me GNOME 3 is different than its predecessor, but looks sleek and polished and looks good on high resolution monitors. Unity expressly comes from a netbook project and a harebrained attempt to shove multimonitor, widescreen setups into a low-res netbook mold. Additionally, it looks like the OS X dock interface (which I heartily dislike), but redesigned and styled by ignoramuses armed with crayons rather than the expert UI designers at Apple.


Gentoo

For a brief while I played around with Gentoo again. I like it. I genuinely enjoy the fiddling I have to do to get a Gentoo system up and running, and I really don’t think there’s so much of it that it’s a serious burden. The emotional appeal of a system that I have customised is great; it’s the comfort of a carpenter whose tools have worn down by pressure and friction to fit his hand alone—I don’t pretend that my managing CFLAGS measurably helps performance for most applications, and even USE flags, though definitely useful, don’t affect me that much. But it’s comfortable and pleasing, as someone who cares about his tools. It’s also pleasantly familiar, as the distro on which I cut my teeth as a regular and moderately competent Linux user.

The problem is chiefly just that while I’m happy, nay, delighted to manage a Gentoo system, I’m not half as happy to manage three of them, and between work desktop, home desktop, and laptop, I would be. That’s too much repetitive work; too much time.

Minor problems include never quite being entirely satisfied either with stable (which is too far behind!) or unstable (which, though rarely, sometimes means a bunch of fudging and masking and version-specific flag management); and at the time when I last tried it, the fact that I was really kind of curious about GNOME 3 and Gentoo had no reasonable way of checking it out—it was faster to try Fedora.

So right now I’m not using Gentoo, but as always when I’m not using Gentoo, I sort of wish I were.


Fedora

My experience with Fedora is mixed. Once I get a Fedora system setup and running, I have no complaints. It’s solid and stable and easy to manage and keep updated, as I expect from a Linux system. They stay up to date with software versions and follow upstream rather than going off on silly, Ubuntu-esque digressions, both of which I appreciate. Running it, then, is a pleasure.

But setting up Fedora is another matter. I’ve done it a few times this year, and while it’s fine when it just works, it—wait, no, I don’t know what that’s like. I actually think setting up Gentoo is more straightforward: It’s a lot of work, but it bloody well works the way the guide tells you it will. Fedora is simple in theory, but never seems to work out of the box.

This is what I’m currently running because frustrating as setup can be, I only have to do it every six months or so at the most, and in between it’s pretty much sunshine. But ye gods! are those intermittent periods ever exasperating! Installing a release version of a distribution should not be this error prone, and the upgrades? Disgraceful.

It’s kind of the antithesis of my view of Ubuntu right now, really. If I could run an Ubuntu installer and end up with a Fedora setup, then I’d be happy. That’s not what happens, though. Instead, what I get when I try to install Fedora (I say try, but there is eventual success), is a series of tales of woe I place behind a cut for your comfort.

Details of my Fedora install and upgrade woes )

Now, I’ll freely acknowledge that I’m a bit of an early adopter if I upgrade to the newest version the same week that it’s released, but I find all this very disappointing in what is supposed to be a release version, having gone through formal alpha, beta, and RC stages, with the final release even pushed back (I think twice) to resolve blockers. This load of issues, on three separate systems, is the result? I’m typing this up on a computer that is now finally running a perfectly beautiful GNOME 3 on Fedora 16, but it really shouldn’t take this much drama to get here. I’d excuse it if I were running Gentoo/unstable (excuse it, but be surprised to find it—the quality of Gentoo’s unstable branch would have to go downhill for that to happen).


Still, having tried the two biggest distributions (Ubuntu and Fedora) and found each wanting in its own way, I’m not sure where to turn next. Linux Mint? It is Ubuntu-based but seems less willfull and control-freaky, and the next version (due any day now) will ship with GNOME 3. Maybe that’s worth a try. openSUSE? Something else entirely?

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