A few weeks ago I linked to an article at Weightology ( Why Is It So Easy To Regain Weight?) that had a discussion of adaptive thermogenesis; i.e., the metabolic penalty that we pay when dieting. That article analyzed a study which found that resting metabolic rate declined in those who had lost weight, more than would be expected just from the reduction in mass. Some of us were speculating in the comments about whether that metabolic penalty was permanent, and if not, how long it might last. The study discussed in the article had measured a year out. In a separate thread in the forum a few weeks or months before that, I'd also gotten into a discussion as to whether there was any evidence that diet composition had an effect on the metabolic penalty. It turns out both of these issues were looked at in a study that was published just a month ago. I don't (yet) have access to the full text, so take this with a grain of salt, but it looks very interesting: Effect of Diet Composition and Weight Loss on Resting Energy Expenditure in the POUNDS LOST StudyThe researchers apparently set up different diet types (high/low protein and high/low fat), and measured body composition and adaptive thermogenesis as a function of the macronutrient composition of the diet. Conclusions: Quote:REE fell significantly after weight loss but was not related to diet composition. Adaptive thermogenesis was evident at 6 months, but not at 24 months. So, if the abstract can be taken at face value (a very huge if), the macronutrient composition of the diet doesn't affect adaptive thermogenesis. In other words, you can't immunize against the metabolic penalty by going low-carb, high-carb, low-fat, high protein, etc. The study also found a metabolic penalty of about 100 calories/day in men and about 55/day in women, roughly in line with the Weightology article study. The penalty was observed at 6 months, but had disappeared by 24 months. So this may be good news after all - it might be the case that if you can sustain your weight loss for two years, you will recover from that metabolic penalty. That still leaves open the bigger issue from the Weightology article, though - whether or not the reduction in NEAT persists after 2 years as well. Reduction in activity level did, after all, account for most of the reduction in daily calorie burn among dieters. The reduction in resting metabolic rate was much smaller - but at least it appears to be temporary.
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3282 kcal
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Rasva: 108,61g | Prot: 194,08g | Hh: 433,36g.
Aamiainen: cocoa roast almonds, tomato, blackberries, blueberries, strawberries, carlson fish oil, optimum strawberry, chobani plain nonfat. Lounas: jack link's original beef jerky, tomatoes, lettuce, olives, chicken breast. Päivällinen: DANNON LIGHT & FIT BLUEBERRY, Frozen Edamame - Soybeans in Pods, tomato, fiber one 80, Milk (2% Lowfat with Added Vitamin A), bountiful morning. Välipalat/Muut: dark chocolate dreams, hunt's sugar free pudding, crunchmaster, plum, krema, dannon light & fit cherry, meijer cottage cheese, dark chocolate dreams, fiber one chewy bar, banana peanut butter, monster rehab, banana, optimum strawberry, 2% milk, vegetable medley, apple, Extra Dessert Delights Sugarfree Gum - Mint Chocolate Chip. lisää...
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Kommentit
I dislike the articles phrasing it as a reduction in activity level. It makes it sound like just sitting on my butt is the reason I am unable to drop the 20# I regained. Then I read this part in the Weightology... "It also means we become more efficient in the activity we do; we expend less calories for the same movement. In fact, 35% of the decrease in activity energy expenditure can be attributed to an increase in efficiency. Overall, we move around less, and we become more efficient at the movements we perform. Combined with a decrease in resting metabolic rate, we end up burning over 400 calories per day less than you would expect for someone of our same height, weight, gender, and body composition" ...That I believe. A fat body used to be running at 6mph carrying 205#s, now it's only got 185#s. It makes sense to me that it could run that same speed and require less engery expenditure, because it was used to working harder all those years. I kinda wondered if that had something to do with why my resting heartrate is so low now.
18 kesä 12 jäseneltä: JessWhatINeeded
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Jess: You're putting your finger an issue I've wondered about. Anecdotally, everyone I know that has lost weight has talked about how much more energetic they've felt after doing so. And I've experienced it too. And yet, the research is consistent - people tend to move less after weight loss. So how does that square? Are we all just fooling ourselves? Or is the research wrong? It might not be either. The increase in efficiency combined with the fact that we have to work less in the first place to move as much mass around could mean that we're doing more activity as a function of time, but because the activity requires a lot fewer calories to power, we could in fact be more active in terms of time spent moving or even discrete instances of movement, but still doing less "activity" from an energy perspective. Want to give me a large grant to study the issue....?
18 kesä 12 jäseneltä: Nimm
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Thanks for the follow-up article. It's nice to see that there's some evidence that the handicap isn't with you forever and it's also a bit lower than I thought. 55 cals a day is something you can easily overcome with a bit of conscious effort, like getting in a 10 minute walk everyday. But, if you aren't careful, that's almost 6 pounds a year in regain, so it all adds up! Intentionally or unintentionally, I've been in maintenance phase for the past 7 months or so and have actually been surprised that I've avoided any real regain, but I've also been reasonably active and still pay attention to what I eat. There are times when I over-indulge but the majority of the time I still restrain my eating. I think the key is to always be conscious of what and how much you're eating and do your best to stick with the good habits you've developed during your weight loss period rather than completely tossing them aside once you've see your goal weight on the scale.
18 kesä 12 jäseneltä: gnat824
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I wish I could give out money. Stuff like this interest me, because I'm personally affected by it. And I like math & stats.
18 kesä 12 jäseneltä: JessWhatINeeded
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Large grant. LOL. but you WOULD be GREAT, Nimm, at a study like that. Is there any chance that our bodies just get used to the type of exercise we do?
20 kesä 12 jäseneltä: Helewis
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I don't have time to read the article at the moment - but your comments look a bit more positive. I think one of the key strategies is, to always weigh yourself, so you can take action when you start 'creeping up' in Weight - so easy to ease up on food and exercise.
20 kesä 12 jäseneltä: Sk1nnyfuture
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Nimm, thanks for bringing the food for thought! I always appreciate learning more about how these things effect my body. I guess it's an attempt for me to understand the rules of the game of weight loss so that I can "win" more effectively! Keep up the great work!
20 kesä 12 jäseneltä: Heidijoy
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