So many interesting comments here.

Lynda, Dean, ItsTheWoo ~ I'm glad there are some boundaries you were all unwilling to cross. I don't want to think any of you would have gone the Kirstie Alley 'Fat Actress' route and considered tapeworms or crack!

******

Regarding if metabolic rate can be too high - I think Traditional Chinese Medicine suggests that there is only so much fuel in the lamp and if we burn brighter, we also burn out quicker.

Personally, I'd choose to cast a little more light these days!

This is a bit of a tangent, but hyperthyroidism is a type of hypermetabolic (fast metabolism) disease. Obviously, those of us with normal (or low) functioning thyroid aren't going to develop this disease by changing diet and exercise, but look at some of these symptoms:

Selected Hyperthyroidism Symptoms & Signs
* Weight loss
* Increased appetite and calorie consumption
* Nervousness
* Restlessness
* Heat intolerance and feeling overwarm
* Increased sweating
* Less need for sleep and sleeping difficulty
* Skin - clammy
* Skin blushing/flushing
* Pulse - fast
* Heart palpitations

Weight loss with the ability to eat more, figit-y, warmer ... doesn't some of these sound like what Dianne and Lynda have posted about?

Starvation Symptoms
This article is about the effects of starvation on behavior and it's implications for Eating Disorders, but there is some interesting information here. Here's an exerpt:

"Various changes reflected an overall slowing of the body's physiological processes. There were decreases in body temperature, heart rate, and respiration, as well as in basal metabolic rate (BMR). BMR is the amount of energy (in calories) that the body requires at rest (i.e., no physical activity) in order to carry out normal physiological processes. It accounts for about two-thirds of the body's total energy needs, with the remainder being used during physical activity. At the end of semistarvation, the men's BMRs had dropped by about 40% from normal levels. This drop, as well as other physical changes, reflects the body's extraordinary ability to adapt to low caloric intake by reducing its need for energy. More recent recent research has shown that metabolic rate is markedly reduced even among dieters who do not have a history of dramatic weight loss (Platte, Wurmser, Wade, Mecheril & Pirke, 1996). During refeeding, Keys et al. found that metabolism speeded up, with those consuming the greatest number of calories experiencing the largest rise in BMR. The group of volunteers who received a relatively small increment in calories during refeeding (400 calories more than during semistarvation) had no rise in BMR for the first 3 weeks. Consuming larger amounts of food caused a sharp increase in the energy burned through metabolic processes."

* Sorry kwikdriver ~ no footnotes this time! Gonna have to go the link.

Starvation is classified into three categories based on caloric intake over time (Frisancho, 1981):

1. Acute - less than 600 calories/day for less than two weeks.

2. Semiacute starvation - less than 1100 calories/day for less than 30 days.

3. Moderate semistarvation - less than 1600 calories/day for as long as 24 weeks.

Doesn't take into account gender, age, height, etc. ... so this must be a very rough guideline. There is a lot of conflicting information on what actually constitutes the caloric cutoffs for a starvation diet. Some researchers consider 50% less than a normal, healthy calorie intake (whatever that is).

My resting pulse is a whopping 46 - 48 BPM, down from 104 - 106.

This isn't a serious contribution to this thread, just a brag, pure and simple. Thanks for setting me up for that.

Lynda

This is the sort of thing I'm looking for. I'll look it over and see what I think when I have some time. One thing in particular I'm curious about is the possibility that the "starvation effect" results in some sort of long term damage to a person's metabolism, beyond the obvious effects of reduced muscle mass, which is quickly remedied by increased eating and weight training anyway.

My basic point, and I'm hoping it will be addressed by this research, is this:

Let's say it's a given that the body has the ability to slow itself down in response to calorie restriction. If that is so, there still must be an optimum point on the calorie consumption/weight loss curve that is almost certainly well below the "non-starvation effect" area, because the body can't slow itself down to zero, or even close to it, but we have the ability to cut calories to zero, or close to it. At what point on the curve do diminishing returns begin to show up? And do they ever outweigh the effects of additional calorie cutbacks?

The stakes, I think, are clear: if there is no long term metabolic effect, then people should cut calories to whatever level they like, as long as they aren't damaging their health in the process. I simply can't imagine the "starvation effect" is so profound that it would nullify large cuts in calories (in fact, if it could people wouldn't starve to death), but rather, for every, say, 100 calories you cut, the body might respond with a what, 50? 25? less? calorie a day scaleback in burning them up. That's a tradeoff I suspect most people would jump on -- as long as they weren't doing themselves harm in the long term.

I hope that made sense. It would help if I had a better background in math, but one must make do with what one has.

Hey kwikdriver ~

Regarding your statement "... reduced muscle mass, which is quickly remedied by increased eating and weight training" - I found this from the original Minnesota study:

"The changes in body fat and muscle in relation to overall body weight during semistarvation and rehabilitation are of considerable interest. [snip] While weight declined about 25%, the percentage of body fat fell almost 70%, and muscle decreased about 40%. Upon refeeding, a greater proportion of the "new weight" was fat; in the eighth month of rehabilitation, the volunteers were at about 100% of their original body weight, but had approximately 140% of their original body fat."

However, who knows what the rehabilitation entailed ... using a moderately-high protein diet and weight training may have resulted in a better result.
It would be interesting to see what that number really would be, huh?


Conversations certainly have strayed off topic!

That is FABULOUS Lynda!

You continue to inspire me all the time ... especially because you are one of the few people who knows the symptoms of a connective tissue disorder first hand.

Keep on braggin'!

They weren't weight training, I can just about guarantee that. I know from personal experience and observation that muscle comes back fast after a layoff and atrophy. I also wouldn't expect the body to rebuild muscle in the absence of need -- that is, without a training regimen. The body is efficient, after all, and muscle, as you know, is calorically expensive to maintain. So the results here don't surprise me in the slightest.



I think the important point is, it isn't 100. And as long as it isn't 100, the only barrier to people going on very low cal diets is the possibility of some kind of long term metabolic damage. I want to read that study you provided, but only when I can really dig in to it. Who knows, maybe it addresses that issue.

I would add that the other barrier -- that I unfortunately am intimately familiar with -- is the possibility of rebound eating. I believe that is the cause behind the fact that most people who lose a lot of weight regain the weight they have lost and frequently regain even more. Our "willpower" can only hold our hunger at bay for so long and eventually most of us give in and eat. Because we have been hungry for so long, we eat too much. This doesn't happen to everyone, but I would be very surprised if there weren't other members of the TDC (in addition to me) who have experienced this phenomenon while following a low calorie diet at some time in their pasts. That's what happened to me every time I went on a low calorie diet in the past and that is why finding low carbing is such a break through to me. I could eat until I was no longer hungry and still lose weight.

For more info on rebound eating check out that Starvation Study link. It's really fascinating if you are willing to plow through it. Under Attitudes and Behavior Related to Food and Eating, there is a bunch of validation for this common experience.

One I'm too familiar with, too.

We've just been talking about the physical effects of very low calorie diets, but I believe the psychological damage can be just as bad ... if not worse.

kwikdriver, can you expand on this?

One of my biggest issues is that I don't want to lose any muscle fiber. That's why I'm taking this slowly. It would be much easier to lose the rest of this weight if I wasn't concerned about retaining my muscles. I know that I had strong muscles just to be able to carry around my heavy body. Is that muscle fiber still there, but just not in use now? If I lose even more muscle, would it come back easily?

I've read that muscle can come back fast and have debated about whether I should just forget about keeping the muscle I have for now and drive myself to goal, and only at that point start building muscle. On the other hand, I've heard (and somewhat experienced) that it is very hard to build new muscle. I had decided to err on the side of caution and not lose the muscle in the first place.

Correct me if I'm wrong, but I don't think any of the current (or close to being) maintainers were trying to keep their muscle mass as big as it was when they were heavy. So I feel to a certain extent that I don't have a TDC role model for what I'm trying to do. I read a lot about this on bodybuilding websites, but they don't really address it from a TDC point of view.

I have my own theory on this (I have a theory on everything ). As someone who went on a lowcarb diet a long time ago, lost about 70 pounds, went off it, and then gained about 150, I know that psychologically, I kept telling myself that I knew how to lose weight now, and that, as soon as I wanted to, I could go on a low carb diet, get rid of all those cravings, and the weight would fall right off. I think almost every day for 8 or 9 years, I told myself I would start induction tomorrow, but today I was going to eat my favorites; unfortunately, my favorite food was "a lot."

Once earlier, I lost a lot of weight, over 100 pounds, to judge by pants sizes, by eating once a day for about 6 months. Then, too, I gained most of the weight back, also telling myself that as soon as I decided to, I would start eating once a day again and lose the weight.

I wonder if that's true for other people. I've seen signs of it reading posts here from people who have "fallen off the wagon" as they say, and are now trying to get back on. The allure of telling yourself you have the magic key to weight loss is a powerful appetite stimulant, or at least it was for me.



No argument from me.

As for hunger-base rebound eating, I just don't get very hungry low carbing, so there's no real feeling of deprivation. In fact, the first time I low carbed I was often eating quite a lot of food (3500 calories a day at times), and so could hardly claim to be starved.


Overall though, I agree that rebound eating is a potential problem. But it's that way whether you go extreme low calorie or not.

Don't fool yourselves into thinking this would be a linear relationship. It most certainly would not be. It would more likely have a "trigger" that at some point will cause the body to go into "low-metabolism" mode. When that mode is hit, there will be a sudden decrease in the basal metabolic rate (my guess). Thus, I speculate that it would entirely be possible, to cut calories by X, but actually gain weight if the drop in metabolic rate more than compensated for X.

However, if you keep cutting calories, then at some point you would overcome the lower metabolic rate and start losing. But of course, there may be several "triggers" along the way lowing your metabolism a step at a time.

There may be many interrelating factors involved here too. For instance, when your body starts shutting down the metabolism, it could be like my Pocket PC going into low-power mode where it runs the processor at a slower speed. But if I run an application that requires more speed, then the Pocket PC is forced to switch back and run at the normal speed.

In my work, my brain goes through times where I have to concentrate a lot more. I think that alone must boost my metabolism, especially since I sit here for long stretches doing it. On other days though, I just can't get my brain to function that well. Perhaps that is a sign that my body is trying to get me to slow down and resisting my attempts to think at a higher level.

And this is where I think attitude actually plays a real role in weight loss. I'm thinking that we often let our body control us, letting it decide when and how much to shut things down. But I think our higher-level self has the ability to override those orders, and set a different plan into action.

I'm thinking that if we "want" something, if we *really* want it, that is when we stop letting our body control us and we start controlling it, figuring out what to do to get it in line. However, this is not easy or a one-time deal. Without knowledge of those puzzle pieces it is easy to get discouraged. Even if we do have the puzzle figured out, we still face each day with the challenge of whether or not we want to be in control that day or just let our bodies plot our course for that day.

This is where the "will" really comes in. It is more than just willpower to make us do a given program or exercise a certain amount. It is the "will" to be in charge of our destiny. Couple that "will" with the "attitude" that your goal is reachable and your body begins to cooperate with you more than fight against you.

A big factor here is knowing you can achieve your goal. That gives you hope and that makes a world of difference. Without hope, I think our bodies don't really take our higher-level commands seriously.

Don't we all know there are times when things just "click"? That last puzzle piece falls into place. That decision is finally squarely in front of us and we know we have to make our choice now. We make the choice and suddenly everything changes. What was really hard before, becomes relatively easy.

But we have to remain in that grove. Our bodies will try to throw us off track. Life will throw us curve balls. The road may get bumpy. But if we remain focused and on track, we just know we'll make it. And it's that "faith" that makes all the difference in the world. No?

It has to be linear, if only from the standpoint of regression (averaged over time). Otherwise people wouldn't starve to death, or people would find themselves gaining weight at, say, 800 calories a day, but able to lose at what, 1200? I can see this happening in the (very) short run, but in the long run, nobody (well, maybe a very small person) lives for long on 800 calories a day, let alone gains weight.

There has to be a curve, it's just that no one has looked for it. I'm sure it's a steep curve at first, and it probably levels out with lower calorie consumption -- but it never goes entirely flat, not when it's averaged out over time. To do so would violate the laws of thermodynamics and probably biology. That's my main point.

I wasn't intentionally managing lean mass, but as you can probably guess, I've been tracking it.

My records on lean mass and body fat only go back to Dec 2002. I started keeping them about a month after I switched from a diabetic diet to CALP.

I had an initial gain of about 5 lbs in lean mass, and then kept that quite steady until Feb 2004 when I went into my focused 100 day weight loss period.

At that point, I had a surge upward about 8 lbs in lean mass, but that returned back to my steady level after 2 months. I'm sure some of that was due to hydration changes related to changing carb levels a bit. A lot of it was due to the fact that I upped the exercise, and was doing most of it as fast walking on hills, tracking elevation changes, and intentionally making as much of my walking more hill climbing than level hiking. The reason my muscle mass dropped back down after 2 months is that I switched from heavy elevation work to more running in place so that I could combine my exercise with family time better. (Running in place watching Dr. Phil with Pat is the ultimate level ground style work out.)

My muscle mass has been pretty level since then, ebbing and flowing over a 3 lb range which would probably match well with cycles of cold and rainy Ohio weather.

I actually track relative changes in body fat rather than the absolute number because I record both weight and body fat first thing in the morning. If you use a Tanita scale (which I think you do) you know from the instructions that the most accurate body fat reading is actually later in the day after body water levels even out. Using a recent afternoon reading (24 % BF), my lean mass would be 114.8 lbs and my body fat would be 36.2 lbs. Using the body fat reading I got at a recent health fair (17.5% BF), which measures off my bony arms instead of foot to foot via my last bit of belly fat, my lean mass would be 124.6 lbs and my body fat would be 26.4 lbs. I'd expect an immersion reading would be somewhere in between.

In my opinion, any muscle mass change I've had during the time I've been tracking data on my LC weight loss has always been clearly related to changes in how muscle intensive my exercise routine has been - except for the initial gain in muscle mass at the start of this that I think is related to improved protein and fat intake.

One other thing - if you are considering a diet/exercise program change to accelerate weight loss and are worried about impact on muscle mass, you could always just try it but keep tracking lean mass. If you set yourself a personal limit of 2 - 3% of your current lean mass lbs being the most lean mass you would be willing to put at risk before you went back to your current plan (that you can trust works for you) you'd still be able to recover any lost muscle mass in a short period of time if things didn't work out.

Lynda

This thread is going off in all sorts of directions and I wonder if we should "spin off" one or more of the topics so others who might be intterested could find them. I have a question that goes back to the "starvation mode" theme a bit earlier. I have been under the impression that extremely low calorie intake damages the heart. In cases of anorexia, for example, I have read that the heart actually shrinks in size and is related to causes of death in some cases. Does anyone know anything more about organ damage due to eating very low calorie over a long period of time?