"Starvation mode", exercise calories, dillema?

You talk a lot about myths, science, evidence, etc. Which is great, but then you just handwaive away the important math of it all:

Just find your approximate BMR (there's a ton of sites out there that do this, go to webMD and put metabolism calculator in, you'll find their tool for TDEE) and multiply by 1.25 (in this example) and you'll get close to your TDEE

I call that a TDEE dartboard.

How can you be so certain of starvation mode hitting or not hitting when it's one wild *kitten* guess as to what your TDEE is?

There are multiple correlations for BMR they vary by up to 20%
The scale factor for activity is LOL ranging from 1.2 - 2.0

But we take all those random *kitten* assumptions and then say if you eat below XXXX you hit starvation mode? What about some other empirical evidence to help guide you - effect on weight loss, sleep quality, etc?

It's important people tighten up their "calories expended" range. Either by tracking all of their data in a spreadsheet to see if they're losing as much weight as they expected, or else going and doing things that make their estimates more accurate - getting BMR tested, buying an HRM, etc.

You talk a lot about myths, science, evidence, etc. Which is great, but then you just handwaive away the important math of it all:

Just find your approximate BMR (there's a ton of sites out there that do this, go to webMD and put metabolism calculator in, you'll find their tool for TDEE) and multiply by 1.25 (in this example) and you'll get close to your TDEE

I call that a TDEE dartboard.

How can you be so certain of starvation mode hitting or not hitting when it's one wild *kitten* guess as to what your TDEE is?

There are multiple correlations for BMR they vary by up to 20%
The scale factor for activity is LOL ranging from 1.2 - 2.0

But we take all those random *kitten* assumptions and then say if you eat below XXXX you hit starvation mode? What about some other empirical evidence to help guide you - effect on weight loss, sleep quality, etc?

It's important people tighten up their "calories expended" range. Either by tracking all of their data in a spreadsheet to see if they're losing as much weight as they expected, or else going and doing things that make their estimates more accurate - getting BMR tested, buying an HRM, etc.

You are exactly right, and I say all the time, if you can't figure out your TDEE, or if you're having problems finding it, you should be tested in a metabolic lab. The reason why I don't give a more precise method for at home testing, is because there is no more precise method. You get as close as you can, try, and tweak as you go. If you don't want to use that, then I'm all for getting your metabolism tested. And they're not wild *kitten* guesses, they're as close as you can get on your own.

You're making generalizations about the TDEE. It's not a dart board, it's a best case estimate based on as many factors as we can nail down. Some things you can't, and that needs to be understood. I don't think anywhere in any of my writing have I said that what I do will be 100% accurate every time, there's no such thing, even Dietitians will tell you that, it's a lot of trial and error.

And I don't base starvation mode on someone's estimate of TDEE, I base it on the hormone levels of the body. When you're body passes certain thresholds, the flow of hormones changes, and this triggers the body's natural famine responses. That's just human physiology.

HOW AND WHERE CAN YOU GET YOUR 'METABOLISM TESTED?' THANKS

I started a ketogenic diet last week and according it MyFitnessPal, was eating 16 to 20% carbs. Was doing and feeling fine until day 4, after walking on my treadmill for appr 1hr. Then I became very depressed and cried a lot. It could have been triggered by something I saw on FB, but more than I would have expected. Could something about the diet have caused this? It lasted till the next day. My husband went and bought me a lava cake and ice cream for my birthday and I actually felt better afterwards. Any connection? Also, I have lost 45 lbs at this point with 13 lbs to go to get to my ideal goal of 110 lbs, I am 5'1" and 51 years old.

SHBoss1673, thank you for such a comprehensive post at the beginning of this thread. I began weight loss about 4 weeks ago and have since began trying to separate fact from myth in the world of diet and exercise, and as I'm sure you know there certainly is a lot of myth out there. I feel the best source of fact, or at least the best we can hope for, is from research journals. Can you please point to me the research article/journal which shows the body entering an absorptive mode following fasted state. Meaning that your body holds onto food while eating in a starved state and prefers storage to feeding the body. I've heard this many times, but just as you, I'm trying to separate fact from myth. I am a 5'10 male weighing 350 and have been on an 800 calorie low carb high protein diet consisting of lean protein and vegetables for 4 weeks. This resulted in 20lbs of weight loss. During this time, I've poured over research papers and studies that have to do with BMR decrease and metabolic changes associated with starvation (less that 50% bmr intake of food). What I've arrived at is that "starvation mode" and the resultant decrease in BMR are largely controlled by decreasing thermogenesis. This will decrease your BMR by a small degree and make you feel cold all the time. But the more obese the person, the lesser suppression in thermogenesis for the same degree of fat depletion in a normal weighted person. ("Adaptive reduction in basal metabolic rate in response to food depreivation in humans: a role for feedback signals from fat stores" Abdul G Dulloo and Jean Jacquet, American Journal of Clinical Nutrition 1998). So in obese people the effects of this "starvation mode" are largely decreased. I've read the book Eat Stop Eat, and then read all of the sources sited in the back as well. Many of these claims for the use of a 24 hour fast or 1 meal a day to increase fat loss do hold up. What I can't find however is studies that specifically demonstrate the greater loss of lean tissue over fat during starvation or semi-starvation. Also, I'd like to find whether nutrition influences the bodies tendency to oxidize fat over lean tissue during a semi-starved state. Meaning, can eating high protein and low carb influence what my body decides to cannibalize. I respect your opinion and admire your passion, but if you would, help me along the path to separate all these myths by stating some sources for your claims.

So, in review. If you know of any of the following, please let me know. They'd allow me to accept the information in your post a lot easier and put to rest some questions I've had for a long time now. My personal research does conflict with yours a bit, and love to read more if you have on hand the below information.

- Source for body favoring an absorptive state after fasting

- Source for body favoring lipogenesis when eating during a fasted state

- Source for body favoring lean tissue catabolism over lipolysis in the obese during starvation.

- And if you have ran across any study that talks about how nutrition effects the balance of lean tissue catabolism and liplysis.

Thanks for writing this. I have a MFP friend that I hope reads this. I don't want to be too pushy, but I know she's not giving her body enough fuel. Luckily, I know she will be seeing an MD soon and is looking for answers. I'm a nobody, but hopefully a professional's opinion will make it click.