Carroll wrote:If someone were to eat less than 500 cal/day for an extended period as long as they are above 5% body fat there is no way they can ruin their metabolism correct?
The 5% is not carved in stone but an estimate of essential fat for a man. A women is estimated to be about 2x that.
The issue is, there is no "starvation mode."
Starvation, yes.
Starvation mode, no.
Let's clarify.
Starvation mode is often used by dieters to explain why they have not lost weight, are not losing weight, or why they have stopped losing weight. They say their body is holding on to the weight because they are eating too few calories and the body has gone into this starvation mode to conserve calories. The solution they give, is to eat more calories, to get the body out of starvation mode so they can resume losing weight.
This is absolutely incorrect.
Keeping everything else the same, you simple can not lose more weight by adding in more calories.
Also, if someone was in the above scenario and the actually ate less, even much less, or even fasted, we all know they would start to lose weight. Yet, according to their reasoning behind the starvation mode, they should actually go further into this mode and not lose anymore weight at all.
Now, if someone consistently consumes a low calorie intake, or is in a negative calorie balance, and gets to a point where they have used up all their reserves of essential fats, they will enter what is known as "starvation" and not "starvation mode". And, they must eat at this time or they will soon die. This is not a weight issue but a life and death issue. And, we know that if they do eat, they will gain weight, not lose weight, as hypothesized in the starvation mode theory.
So, starvation mode does not exist. Starvation does and anyone can reach that point.
In starvation mode, they say you must eat more than you are, so you will lose more weight, which is absolutely incorrect.
In starvation, you must eat or you will die and you will gain weight as a result of eating.
You can see how they have completely misrepresented the actual issue of starvation into their crazy theory of the starvation mode.
Carroll wrote:Of course I'm sure loss of lean body muscle as well as less energy expended with digestion would mean lower BMR,
RMR/BMR is related to mass, not just lean body mass, so as there is less of you, your RMR will drop accordingly. TEF, the thermal effect of food, will also be lower when one eats less, but TEF Is not part of RMR or BMR and is a seperate component of TEE.
When you gain the weight back, your RMR will also increase accordingly. You can not "ruin" your metabolism.
Carroll wrote:however even after many weeks of such a low calorie diet once a higher calorie diet is returned to the metabolism will still be the same, right?
Yes, as your mass increases, your RMR will increase accordingly.
In Health
Jeff