This is a common misunderstanding of the "starvation mode" evidence. Starvation mode is not about preventing starvation, it's about slowing the process.

The longevity of the average (and unusually long-lived) anorexics are actually often used to support the evidence of starvation mode. Anorexia victims often do lose weight until they starve to death, but many survive much longer than can be attributed to by an unimpaired metabolism. It's not a mystery that anorexics starve to death, but it is a mystery as to how some of them can take so long to do it.

If you take someone who has never been on a single diet and stop feeding them, they will tend (on average) starve to death much sooner than a person of the same weight who has a history of yoyo dieting or bulimic behavior.

In theory, anorexics should die just as fast... but they don't (well some of them do, but many of them don't). Instead, what often happens is that the body stops "wasting" energy (calories) on "unnecessary" processes. First the anorexic will lose their hair, but then later they will develop a downy fur-like covering of hair all over their body (the prevailing theory is that the body does this to preserve body heat... so that fewer calories need to be spent on maintaining a safe body temperature... body temperature also tends to drop several degrees. This isn't great for the body for several reasons, but it does prolong the starvation process. This is starvation mode (survival mode would be a better term - because starvation is not prevented only postponed/prolonged).





Again, because "starvation mode" doesn't prevent starvation, it only delays/prolongs it. There's nothing magical about metabolic decline. The medical community understands many incidents and ways in which metabolism can slow (and that's all starvation mode is.... slowed metabolism. There seems to be a great variation among individuals, and genetics may be involved. Some people may have inherited very resilient metabolism that slow and speed up as the environment warrants. Or perhaps environmental triggers account for the difference... but many of these metabolic changes are well understood... some are not).



Again, this reflects a misunderstanding of starvation mode. Starvation mode doesn't prevent starvation/weight loss, it only slows the process. And people who have gastric bypass do lose weight, but not at the speed that one would expect if their metabolism was not trying to compensate.

And again, there's a lot of difference from person to person. Two people with the same starting weight, same surgery, and same diet/calorie intake can lose weight at very different paces. Some lose extremely rapidly, some do not.

And another way in which gastric bypass patients experiences actually support "starvation" (or survival) mode is the number of patients who gain all their weight back and sometimes even more.

Because of the amount of digestive system removed, it should be virtually impossible for a person to regain all of the weight after surgery (and for many of the surgeries, up to 60% of patients regain all their weight if not more). In theory, if metabolism were NOT adversely affected, there would be no way to explain this weight gain (at least not without the person eating tons more than they did before the surgery) (because the rerouting of the digestive system prevents many nutrients and calories from being absorbed).

But that's not what happens. The person doesn't return to their pre-surgery eating. Their eating habits backslide partially, but their weight backslides totally (and sometimes more). Their "new" post-surgery metabolism is often much slower than their pre-surgery metabolism. THIS is evidence of "survival mode."

Starvation mode makes it sound like a person becomes starvation-proof, and they don't. Deprive people of food long enough and severely enough and eventually they die... but take dozens of people of the same weight and fat/muscle rations and starve them to the same degree and some will take weeks to die. Some will take months to die. And some will take years to die. "Survival Mode" may explain why some people die quickly, and some die slowly on the same diet.

The medical researchers understand some of the mechanisms by which metabolism can slow to prolong survival (which is why survival mode is a better description than starvation mode), and others are a mystery. Some believe the traits are inherited, others believe they are triggered by the environment (others argue that both a genetic trait and a triggering event in the environment are needed).


All this does not mean "eat more" is valid advice for all weight loss stalls, but there's ample evidence that the calories out portion of the equation is just as variable as the calories in. You can control your calorie intake, but it's much harder to control your calorie expenditures, especially since you can't choose to force your body to spend calories on body temperature or immune function.

There's a lot more variability in weight loss experience than can be accounted for without metabolic conservation of some kind occuring. Maybe starvation mode is not the best name for it, but that doesn't mean it doesn't exist.

That was an excellent rebuttal, Kaplods! Saved my fingers to have you take it on and type it

This was a very informative thread. Thank you everyone.

Like I've said before, this would be a great metabolic process if it were true. Someone would make millions in book sales with that slogan. "Lose weight.....by eating more!" But I have my suspicions that this myth is propagated by those who really don't know anything about dieting or have not been successful at it and haven't seen results. Perhaps this fallacy is perpetuated by those who don't want to eat less.

It's just a biological fact - if one expends more calories than one brings in, one will lose/burn fat. How is it that no fat is used if there's a calorie deficit? Where would the body be getting its fuel? All the free and stored carbs (not stored fat) have already been used up at that point. There's only one other source of fuel (and it won't be the muscles, since the body uses its fuel in a sequential process - glucose, stored glycogen, fat, muscle).

More on the "starvation mode" myth.

http://www.dailymail.co.uk/health/ar...raight-on.html

http://caloriecount.about.com/forums...tarvation-mode


Nice post here about it, particularly Lyle McDonald's commentary.

Good call JohnP, you're right. "Weight" would have been more appropriate there than "fat."

What I know for sure is this:

I didn't get up to 192 lb by "not eating enough".

Shapedself and Jossfit both included excellent articles in their posts - if someone breezed by the links I highly recommend they backtrack and take a gander.

I agree 100% with this post. Tall, short, fat or thin, we can't defeat the laws of thermodynamics.

F.

<<Starvation mode doesn't prevent starvation/weight loss, it only slows the process. >>

I think this is key. A lot of people maintain that you actually STOP losing weight if you go below a certain amount of calories. From what I've read and experienced, you don't stop, you just lose less quickly than expected from your calorie intake.

F.

I agree both with the original poster and with this post I am quoting from JohnP.

And to kick in yet another of my opinions lol, I think the idea of net calories (e.g., that you can eat back some number of calories that you theoretically have exercised off and thus lose weight) is not a good idea at all, because while it may be true and I believe it is true that weight comes down to calories in/calories out, a lot of factors go into that. Plus, you can theorize and measure and use devices, etc., but it is very hard, IMO, to get an exact number that represents how many calories an individual is burning doing exercise.

Not only that, but so many people start to say "I've gained weight... is it starvation mode?!"

Does that make ANY sense to anyone? Really??

Unfortunately, because "starvation mode" is poorly understood, and considered controversial, the sides of the debate end up polarized, and extreme (and sometimes ridiculous) arguments are thrown about rather than the middle-ground truth that the scientifically gathered evidence would support.

Instead of saying metabolic slowing is possible and can happen to some people in very specific circumstances, the argument instead becomes "it never happens in any circumstances to anybody, ever" vs "it happens all the time and can happen to anyone, anytime, at the smallest provocation, such as one missed meal, or eating 100 calories less than one "should."

There's no magic to metabolic slowing, it just means there's a point of diminishing returns. Just because 1500 calories works well for you (lets assume for sake of argument) it doesn't necessarily mean that you'll lose much more on1000 calories (that is you may not lose the full pound more you "should" if metabolism were unaffected).

It would be great if survival mode didn't exist, that is if metabolism weren't affected by severe calorie restriction, because that would mean that to lose weight, we could simply stop eating altogether until we reached our desired weight. Then when re reached our goal weight, we could just start eating again. And we could do it over and over again without impacting our metabolism.

Nice theory, but doesn't seem to work in reality that way. There's been some studies that has found that dieters, especially chronic dieters require fewer calories to maintain their weights than people with no dieting history. Some debate existed as to whether these people (the veteran dieters) always had had slower metabolism or whether the dieting actually was responsible. More recent evidence suggests that the metabolic decline is the result of the dieting (and may be permanent, there haven't been enough long-term studies to know how long the metabolic slow-down lasts. That too may vary tremendously from individual to individual).

Dismissing the survival mode evidence is just as dangerous as believing it accounts for every weight loss stall and the solution to weight loss stalls are always "increase calories," but likewise the solution to stalled or slower-than-wished-for weight loss is not necessarily "eat less." Sometimes "work smarter," is the solution rather than "work harder."


Also a simple "increase calories" is rarely going to be sufficient if a person is eating too little. Instead the advice is more like, "eat a little more, so that you can exercise a lot more."

If we believe that our metabolic rate never changes then calorie intake is all that's important. You don't have to get good sleep. You don't have to reduce stress. You don't have to exercise more (you can, but you don't have to) you just have to eat less.

But eating is only one part of the equation, and starvation diets affect both sides of the equation. Perhaps the simplest of restriction effects on metabolism can be explained just by simple fatigue. If you cut calories too drastically, severe fatigue is a very common side effect. It can be difficult to exercise or even be reasonably active with this kind of fatigue.

So if eating 200 calories more can help you burn an extra 400 calories, you can come out ahead.

Will eating 200 calories more help you burn an extra 400? There's no way to tell except my experimenting.

I was extremely surprised to learn that cutting 500 calories didn't always result in losing an extra pound each week (or even averaged out over the course of several months). Ever since I understood the math in high school, I wanted to assume that metabolism was a constant - but it isn't. The calorie out part of the question is variable, and to find the variables you have to experiment (the research evidence suggests that stress, sleep quality/quantity, calorie restriction, unbalanced diet, activity level, genetics... are some of the variables that can affect the calorie-out part of the equation).

It would be awesome if metabolism were a constant, but it just isn't.

Yes it's true that most people don't get fat from eating too little, however that doesn't mean that eating 500 calories is better (and one pound per week better) than eating 1000 calories. There's a point of diminishing returns in which cutting calories further doesn't yield much if any advantage (and can have significant deleterious effects).

"Eat more" isn't a solution unless it allows and encourages you to also "move more."

I never know where to stand on this. We're much too complex to fit into boxes and categories and say that one thing is 100% true for everyone.

Can you waste away? Of course! We know this. Our bodies are complicated though and generally will find ways to combat whatever curveballs we tend to throw at it.

I'll offer up myself as an example, but not necessarily as proof of "starvation mode" but that a lower calorie count can result in metabolic slowdown.

When I hit 125 pounds I decided I was done losing weight. I immediately increased my calories by about 400-500 per day. I lost weight even faster. Not immediately mind you, but I did drop 5 pounds very quickly! I was shocked.

I also noticed that I was no longer freezing all the time. I am still colder than when I was 200ish pounds, but in weight loss mode I was always chilled to the bone. Now I am forgoing jackets on cold days like I did when I was at my starting weight.

This is all anecdotal of course, so make of it what you will. Another person could certainly do exactly what I did and experience something else entirely.