XKCD Does Science. Do not be blinded by it.
Yes, that headline is an almost gratuitously nerdy way of saying, “A recent study published in the New England Journal of Medicine shows very little difference in weight loss based on what you eat, as long as you eat less of it.” Okay, that’s a bit of an over-simplification, but this particular study, of more than 800 participants over a two-year period, certainly appears to take the wind out of the sails of diet programs that proclaim “X is bad, get rid of all of it!” or “Eating a diet high in Y helps you lose more weight!”
To which the study’s authors could presumably reply, “O RLY?”
Def Check:
Macronutrient Breakdown: Percentage of total caloric intake derived from carbohydrates, protein, and fat.
Okay, so what? “Eat less and exercise more” isn’t news — the participants in the study were all given the same 750 calorie reduction in their daily allotment of healthful chow. But seeing how (and if) four different macronutrient distributions affected the outcome for folks who began the program overweight is interesting, at least if you’re a stat geek like me.
In a nutshell, it didn’t matter what folks ate; everyone in the program lost weight, and roughly the same amount of it. Poring over the results more close shows that the subjects getting the highest-carbohydrate diet (65% of their calories from carbs) lost the least weight, but the folks getting 55% from carbs lost the most. The folks getting the bulk of their calories from fats (40%, regardless of their other macronutrient ratio) were pretty much all in the same boat, between the two carb-heavy groups.
I’ll tackle the most obvious conclusion to be drawn from the GRAPHS YES GRAPHS I LOVE GRAPHS data presented first: participants who stayed on the program for the full two years lost more weight than those who didn’t, and their waists shrank more. However, wrapping a little bit of cloud around that silver lining is the fact that the majority of the weight loss took place in the first six months, and in almost all cases, regardless of which dietary program subjects were using, participants gained back some weight and waist size the second year, rather than continue losing it.
That italicized bit, in conjunction with the statistics about how much weight folks lost, leads me to suspect that the lower caloric intake was enough to maintain a weight around where folks began to gain it back (this is why programs like Weight Watchers adjust the daily POINTS allowed to the bodyweight of each person — if you weigh less, you don’t need/get to eat as much).
But what about the big premise, that reduced calories alone are enough to help folks lose weight? True, as far as it goes.
On the whole, those participants who went to a larger number of followup and/or support meetings lost more weight than those who didn’t. Possibly more compelling is the fact that the folks who went to a greater number of followup sessions only gained back about 20% as much weight in the second year of the program as those who didn’t.
No matter what sort of health or nutrition plan you choose — whether it’s popular diet programs like Weight Watchers, or Atkins, or South Beach or Zone; or more hardcore fitness-and-diet programs like P90X or Velocity Diet 3.0 (which I will be undertaking myself, beginning June 1st) — dedication to it, whatever it is, is the number-one recipe for success.
Being committed to a program, and having guidance and encouragement helps folks succeed. Obvious conclusion is obvious.
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Hey, I’m a friend of Rob’s from Boston.
My brother and his GF have been doing P90X for a couple of months now and are very pleased with it. It seems that once folks get started on it they are definitely sucked in, just a warning.
I’ve been doing a lot of reading about weight loss vs. over health/strength and a “traditional” diet versus more modern, processed foods. I’m not sure if any of you guys have any interest in those topics or will be touching on any of them here, but as I try and get my own butt in gear and get more strength building exercise into my diet, the food properties relative to all of this are very interesting.
Thanks for taking the time to keep this blog going (everyone)!
I suspect that we’ll be touching on all of those things, probably from a couple of different perspectives.
As you’ve probably noticed, even though we’re all on the same team, and are all RL friends, we don’t always agree on everything, or have the same reaction to something we happen upon – Mike’s “Different Strokes” column was based on the same NEJM study.
Which is Rafe’s polite way of pointing out that I didn’t properly “claim” the story when I wrote it and didn’t point out that I already had until after he was done.
To Jodi – a guy I know through work is doing PX90, he’s about 90 days in, lost 35 lbs, looks 10 yrs younger. He’s a big fan. I’ll be interested to hear how you and yours like it.
It’s a little high impact for me.
To Rafe – I hadn’t heard of the Velocity Diet. From a quick look at the website, seems like there’s a lot of supplements involved? I’m hoping you catalog your experience here so we can learn more about it.
If you wanted to re-brand VD3, you could call it the “George Jetson Program,” because you don’t eat anything but capsules and various shakes in lieu of meals, except for once a week.
Despite that, it’s actually not all that bad; you just need discipline and a couple of drink shakers.
I did a watered-down version of it in March & April (entries tagged “velocity diet” on my personal blog); I’m aiming to be better about adhering to the full regimen this time around. But, yes – it won’t quite be “live-blogging the apocalypse” or anything that exciting, but there will be handy charts, graphs, and as many four-letter words as I can slip past Mike.