What the heck is metabolic adaptation??
Well...when anyone restricts calories and eats less energy than they burn, their metabolism begins to adapt by slowing down (a.k.a burn fewer calories).
This is one of the reasons that your progress can plateau.
It's why crash diets don't work.
The typical diet scenario is a nightmare for your metabolism.
What usually happens:
1) dramatic reduction in calorie intake (often 800-1100 calories)…
...often combined with
2) dramatic increase in exercise/ energy output.
Once again—anytime we cut calories our metabolism begins to slow down.
The more extreme the calorie restriction, the faster and greater the down-regulation of our metabolism.
So when we dramatically decrease calorie intake and our metabolism finally slows down enough make calories-in equal with calories-out...there is no longer a caloric deficit and weight loss plateaus.
See what we're saying?
This plateau is often met with further calorie reduction or more exercise, which only results in....
...you guessed it: more metabolic slowdown.
(You're so smart).
AND because such restrictive low-calorie diets are almost impossible to follow...
...eventually we can’t take the misery anymore and we tap out.
And then we typically go in the total opposite direction--dramatically increasing calorie intake overnight
(because we are humans who have been living in extreme deprivation).
Now because we slowed down our metabolism (a.k.a. our daily calorie balance)...and now we are going way over...the result is rapid fat storage!!!
Often beyond the pre-diet body fat levels (meaning we end up more overweight than when started dieting in the first place).
What’s going on here is very simple:
people who diet like this have systematically crashed their metabolic rates and then overloaded their bodies with way more calories than they are burning...
...and the body’s response to this is to store much of the excess calories as fat.
So then we end up more overweight than when we started along with a slower metabolism.
If we repeat this cycle a few times..
...we can find themselves in a really bad place metabolically:
...eating very little food to maintain a high body fat percentage we don't want.
This process of dramatically and chronically slowing the metabolic down goes beyond just metabolic adaptation and is often referred to as “metabolic damage.”
Let’s go over this scenario with numbers (like a weight loss story problem):
Mary is a moderately active 40 year old woman, 5’7”, 190 pounds.
Her BMR is around 1600/cal per day, with an activity level of 1.35 which puts her estimated TDEE at 2170 calories.
She wants to lose 40 pounds.
To achieve this she starts an extreme low calorie diet--down to 1100 calories.
When she plateaus (which she soon will) she will have to slash calories below 1100 calories.
IF there is any movement at all, her next plateau will come even faster--but she will probably do it because she is so impatient to see loss.
When the next plateau occurs she has been so deprived, overwhelmed with cravings and now beyond discouraged that she quits.
And she goes directly for the high calorie foods she’s been craving intensely: the pizza, the ice cream, the candy, the chips.
But because she has slowed her metabolism/ calorie balance to 1100 calories or less--she will be immediately putting herself into a big calorie surplus.
The weight will be back on in a hot, hot second.
Why does this happen?
What can we do about it?
Stay tuned for the next post in this Metabolic Adaptation Series!
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